I read somewhere that the chances of being born on February 29th are 1 in 1,461. That is not hard to work out in your head. Since for the rest of us, there is a 1 in 365 chance of being born on any given day, you just multiply by four to get the odds for those lucky leap-yearers. I guess any good parent would make provision for the "missed birthdays" that occur in between and that many would opt for the 28th, since the following day is March 1, an entirely different month. But then some might argue that since they didn't exist on the 28th, the following day better represents their nativity.

This is not a question that has exercised the minds of great thinkers and philosophers over the ages. We cannot help but travel around the Sun in the allotted time, with the necessary correction every four years. But it is an arbitrary measure of sorts. We could have set up an Earth year based on our relationship to other heavenly bodies, though this may have been chaotic, or perhaps one year could have been the measure of how long it takes our solar system to do a circuit of the galaxy. That would be a very long year, about 230 million years, I believe.

Best to leave things as they are.