How to Communicate With a Difficult Co-Parent

Most communication advice assumes goodwill on both sides. It doesn't hold up well against a co-parent whose messages are designed to provoke a reaction, and generic advice like "stay calm" doesn't give you much to actually do in the moment. Two specific techniques, BIFF and gray rock, are built for exactly this situation.

The BIFF method

Developed by attorney and mediator Bill Eddy for high-conflict communication, BIFF stands for Brief, Informative, Friendly, Firm:

• Brief. A few sentences, not a paragraph. Long replies give a provocative message more to react to.
• Informative. Stick to the facts the other person actually needs, a time, a date, a decision, nothing more.
• Friendly. A neutral, courteous tone, even if the message you're replying to wasn't. This isn't about being warm, it's about not giving the exchange anything to escalate against.
• Firm. End the message in a way that doesn't invite further debate, state the fact or decision and stop, rather than defending, explaining, or re-litigating.

BIFF works well for messages that do need a reply, a schedule question, a decision about the kids, something with a real deadline. It keeps the response clean, factual, and easy to stand behind if it's ever read back later, by a mediator, a co-parent, or a court.

The gray rock method

Gray rock is a different tool for a different situation: when a message doesn't actually require a substantive reply and is mainly designed to provoke one. The idea is to become as unremarkable and low-reaction as a gray rock, giving the other person nothing to escalate against because there's nothing there to engage with.

Use gray rock carefully, though, particularly during an active custody matter. Going silent or giving one-word non-answers can read as uncooperative or evasive if the exchange is ever reviewed by a mediator or a judge, silence isn't the same as neutrality in that context. Gray rock fits situations where a response genuinely isn't required. When one is, BIFF is generally the safer choice, since it produces an actual, documented, reasonable reply rather than an absence of one.

Which one to use, and when

• A message needs a real answer (a schedule change, a decision, information about the kids), use BIFF.
• A message doesn't need a response at all (a jab, an attempt to relitigate a settled issue, something clearly designed to provoke), consider gray rock, or simply don't reply.
• Unsure which one applies? Default to BIFF. A brief, factual, documented reply is rarely the wrong call, an absence of any reply sometimes is.

Why the written record matters here

Both techniques work better, and matter more, when the exchange happens somewhere that keeps an accurate, unedited record. A calm, factual BIFF reply is only useful as a record if it can't be misquoted or selectively screenshotted later, which is a large part of why tamper-evident, append-only messaging is worth using for this kind of communication specifically, not just for convenience.

Put it into a written plan

Techniques help in the moment, but a detailed parenting plan that spells out decisions and expectations in advance reduces how often you need them, see high-conflict co-parenting for the broader structural changes that tend to help alongside these communication techniques.