anyone's birthday is on Feb.29 (one time every four years)

Really reminds me of the Pirates of Penzance. If you don't know the story, Frederic is accidentally apprenticed to a band of pirates (instead of a pilot) and gets to leave on his 21st birthday. Shortly after he leaves (and teams up with the police to kill all the pirates), the pirate king comes to him... "For some ridiculous reason, to which, however, I’ve no desire to be disloyal, Some person in authority, I don’t know who, very likely the Astronomer Royal, Has decided that, although for such a beastly month as February, twenty-eight days as a rule are plenty, One year in every four his days shall be reckoned as nine and twenty. Through some singular coincidence – I shouldn’t be surprised if it were owing to the agency of an ill-natured fairy – You are the victim of this clumsy arrangement, having been born in leap-year, on the twenty-ninth of February; And so, by a simple arithmetical process, you’ll easily discover, That though you’ve lived twenty-one years, yet, if we go by birthdays, you’re only five and a little bit over!" So he has to rejoin the pirates. Sucks to be him.

One of my friends growing up was born on Feb 29, 1978. Growing up I thought it was kind of cool that she only had a birthday every 4 years. She always celebrated her birthday on the 28th on the years that she didn't have a birthday. It is a very unique birthday and I'm sure your baby will think so too when he/she gets old enough to know what it means. Congrats on your baby!