I was billing hours while my wife was in labor (it's actually a pretty long and boring process). My kid was almost certainly in daycare when she took her first steps. She won't remember anything that happens before four or five. Whether I'm there for any particular random milestone only has the importance that I assign to it mentally. Obviously kids want your time and you need time with them. The best part of my day is when my daughter toddles up to me when I get home. But kids are usually really flexible. You don't have to be there for artificial milestones just because some parenting magazine hypes them up.