Birthdays

At a birthday party (of your spouse, or that of a friend or family member - it works for everyone). Do be subtle and use emotion.

After everyone has celebrated the anniversary tell the interested party that someone else wants to congratulate him or her: put his hand on your belly, and say "Happy birthday dad" (or grandma / grandfather / uncle, according to the person who is celebrating the birthday).

This announcement will certainly make your loved ones' hearts melt, and the moment will remain etched in their memories.