The information-sharing minimum

Thursday morning. You're scrolling back through three weeks of messages between you and your Co-Parent, looking for whether you ever told them about the parent-teacher meeting that's scheduled for next Wednesday.

You can't find it. You start typing the message now, mid-morning, on a Thursday, ten days before the meeting. You think about what else they might not know about. The orthodontist appointment from last week (you mentioned it; they replied; that one's covered). The friend's birthday party your child has been invited to (you haven't mentioned it; it's three weeks out). The school's new pickup policy (the school sent an email; you don't know if they read it).

You start a list in your head. The list keeps growing. Some of these things they need to know. Some they probably already know. Some they'd rather not be told about. You can feel the familiar uncertainty: how much is too much, how little is too little, and who decides.

This article is about the answer.

What this article is about

This article is the last v1 cornerstone of the co-parent communication module. The first three articles addressed how messages should land. This one addresses what messages should contain.

The principle is this. There is a specific category of information your Co-Parent needs from you, and there is a specific category of information that doesn't need to flow between you. The skill is knowing the difference.

Too little information is a real cost. Your Co-Parent can't do their part if they don't know what's happening. Too much information is also a real cost, less obvious but corrosive: it pollutes the channel, it spends both parents' attention, and it tends to be the place where emotional spillover hides.

The article covers four things. The minimum (what must be shared). The maximum (what shouldn't be). Where the boundary lives. And the structural tools that let the minimum happen without you having to think about it.

The minimum

There are five categories of information that must flow reliably between co-parents. The list is shorter than most parents realise.

Schedule changes. Any deviation from the agreed schedule. Running late. Need to swap a day. Will be away for a fortnight in July. If your default pattern is the same Monday-to-Wednesday and Thursday-to-Sunday every week, anything that differs from that is information. If your default pattern is more bespoke, the deviations are still the items that need communication. The default itself doesn't need to be re-communicated.

Health. Anything more than a minor cold. New symptoms. Appointments. Medications. Prescriptions. Allergic reactions. Vaccinations. Doctor's notes. Hospital visits. If the next adult to be alone with the child needs to know to handle a situation, the next adult needs to know.

School communications. Emails from the school. Form requests. Permission slips. Notifications. Report cards. Meeting invitations. Most schools will copy both parents on official communications if asked; do this once at the start of each year and then most of this category becomes automatic. The school's email is the source; your job is to make sure both parents are on the list.

Social engagements that affect logistics. Birthday parties. Sleepovers. Friend invitations that fall on your Co-Parent's days. Activities that have implications for the schedule. Not every social engagement; only the ones that intersect with logistics. If a friend comes for an afternoon to your house on your day, no information needs to flow. If a friend has invited your child to a sleepover that crosses a handover, information flows.

Concerns that are emerging. Something new in the child's behaviour. A friend group shift that's worth watching. A teacher's flag. A pattern at home that hasn't yet become anything but might. This is the hardest category to calibrate. Err on the side of telling. Most concerns turn out to be nothing. The ones that turn out to be something benefit from both parents having had the warning early.

That's the minimum. Five categories. Almost everything operational fits inside them.

The maximum

The other side of the boundary is just as important. Several categories of information shouldn't flow routinely.

Your assessment of their parenting. What you think they should be doing. What you think they're doing wrong. The advice you'd give if asked. None of this is information the other person needs. Even when they're genuinely making a choice you'd make differently, your sending the assessment doesn't help; it just creates defensiveness. The exception is if a child-safety issue is at stake; that has its own protocols (Module 09 and Module 11 cover this). For everything else, the assessment stays with you.

Your emotional reactions to their parenting. A separate category. You felt frustrated. You felt hurt. You felt judged. These are real feelings. They have appropriate places to be processed (Article 03 covered this). The text thread with your Co-Parent isn't one of those places. Sending an emotional reaction as if it were information turns the channel into something else.

Your relationship status. Whether you're dating. Whether you're not dating. Whether things with someone are getting more serious. Module 12 covers the specific moment when new partners need to be introduced into the co-parent conversation. Before that moment, your romantic life is yours.

Your work life beyond what affects logistics. A busy week. A stressful project. A new colleague situation. None of this is information for the Co-Parent channel unless it affects the child. Travelling for work next Wednesday affects the child. Frustrated with my boss doesn't.

Anything about your child that came in confidence. As children get older, they share things with each parent that they may not have shared with the other. The default is to honour the confidence unless safety is at stake. The child telling you about a friendship struggle in confidence is not information the Co-Parent needs unless the struggle is at the safety threshold. The child trusting one parent with something is part of how the child differentiates the relationships. That trust is not yours to share, even with your Co-Parent.

Long historical context. If a current situation reminds you of something that happened three years ago, the three-years-ago thing isn't information about the current situation. It's pattern-recognition for you. The Co-Parent doesn't need the historical reference. Sending it makes the channel feel like a record-keeping exercise.

Where the boundary lives

When you're not sure whether something falls in the minimum or in the maximum, two tests usually settle it.

The co-worker test. Would you tell a competent professional colleague this information in a one-line update? Co-parenting, mechanically, has the texture of working alongside a colleague on a complex shared project. The information that flows between competent colleagues is operational, current, brief, and useful. The information that doesn't flow includes feelings, opinions, history, and editorial. Apply the same filter here. The colleague isn't a friend. They're someone you do the work with. Information serves the work.

The five-year reread test. If your child read this message five years from now, would the information in it look like something a reasonable parent would have shared with the other, in the service of taking good care of them? If yes, it belongs. If the message reads more like a record of how-you-felt-about-what-they-did, it doesn't.

Both tests come out the same way for almost every borderline message. Operational, brief, present-focused: send. Emotional, opinionated, historical, editorial: don't.

When silence is information

A specific failure mode: not sending information because you're upset and you want the other person to find out.

This pattern is common and damaging. You know the school has sent a notification. You know they might not have seen it. You decide not to flag it, partly because they should have read their own email, partly because you're frustrated with something else entirely. The child's life gets less well managed. Your Co-Parent eventually finds out and feels the small targeted gap.

The damage compounds. Once you've started using silence as a way to communicate displeasure, the other person learns to expect omissions and starts double-checking everything. The channel becomes high-friction even though almost no actual information is moving. Both of you are now spending energy on what wasn't said.

The discipline: send the minimum reliably regardless of how you feel about the other person on any given day. The five categories above flow whether or not you're getting along this week. Silence isn't allowed to become a tool.

The structural tools that do most of the work

Most of the minimum can be handled by structures that don't require ongoing communication discipline. A few worth setting up early.

Both parents on every school list. Email both parents on each child's class teacher. Sign both parents up for the school portal. Sign both parents up for each activity's contact list. The school then communicates the same thing to both of you simultaneously. You don't have to forward; you don't have to flag.

A shared calendar for child-events. One calendar both of you maintain. School holidays, term dates, doctor's appointments, activities, birthday parties, sleepovers. Both of you have read-and-write access. When something gets added, both of you see it. The calendar becomes the source of truth; the messaging thread is just for live exceptions.

A shared note for ongoing things. Allergies. Medications. Sizes. Friends' parents' names and contact details. Any persistent information that both parents need. Updated as needed. The note replaces the slow-leaking version of this information being asked for repeatedly via messages.

A monthly fifteen-minute call. Article 11 of Module 07 covered this for money; an equivalent works for logistics. Once a month, fifteen minutes, a brief look at the upcoming month. Anything bigger gets named. Most of the minimum information for a month can be exchanged in this single call, leaving the rest of the month for exceptions only.

These structures don't replace the messaging channel. They thin it. With these in place, most weeks have one or two operational messages between the parents and that's it. The channel stops being the place where everything happens.

The closing

Thursday morning, ten days before the parent-teacher meeting. You finally type the message.

Hi. Parent-teacher meeting next Wednesday 4pm. Are you free? I can go if you can't, but I think we should both try.

You read it once. You send.

The reply comes in thirty minutes. Yes, I can. Want me to confirm with the school? You reply: Yes, please. Thanks. They reply: Done.

The parent-teacher meeting is on the shared calendar by lunchtime. The friend's birthday party will go on the calendar this afternoon when you remember to add it. The school's new pickup policy will be in their inbox already; they read their own email.

This is what the information-sharing minimum looks like, in practice. Not because you've worked hard at it. Because the structures around it are doing most of the work, and the small remaining decisions sit inside a clear principle.

The principle was always simple. Your Co-Parent needs to know what they need to know to do their job. They don't need anything else.

Two adults, doing one job, with the minimum information flowing reliably between them, and almost none of the rest.

This is the structure inside which co-parenting becomes possible. Not because it removes the difficulty. Because it sets the difficulty down, every day, instead of carrying it forward into the next message.

And the next message, in the structure that's working, is mostly going to be about a parent-teacher meeting.

Which is, in the end, exactly what it should be about.