You say it's your birthday, It's my birthday too

My baby turns three tomorrow.  How is that possible?  Ok, I get that it's possible for him to turn three.  It feels like he's been around forever, so I don't doubt that it's been at least three years - sometimes it feels like 18 years and can't he go to college already - but how on earth am I so old that my baby, THE baby, turns three?  Huh, maybe this is really about the fact that my birthday is on Sunday.