Rebuild the missing context
Assume the recipient will not remember every date, promise, or earlier conversation. For a message about how to congratulate someone on buying a home, use this factual base: name the milestone and, when you know it, the effort or meaning behind it.
Say what needs to happen next
State the decision, information, or practical action you need and include a real deadline only when one exists. Offer warm recognition and let the recipient decide whether they want a call, visit, gift, or quiet celebration. Make the immediate next step clear enough that the recipient can answer without reconstructing the entire history.
Avoid making urgency into pressure
Do not make assumptions about pregnancy, money, relationships, health, or what the achievement should mean next. Follow the person's lead on privacy before sharing their news or photos with anyone else. Do not make the other person responsible for reducing the discomfort that prompted you to write.