So weird, we had our 2nd boy on Monday (our first boy is 2)
Our first is the world to us, we were pretty much told we couldn't have children so he was a little miracle, I had the same fears and also fears of leaving the first out and how he would feel but he's taken to is all amazingly, kids understand more than you think and I've found the more you explain situations to them they are better prepared.
As far as time spent goes, I'm a savage workaholic (have to be) but my little man thinks the world of me, its quality time not quantity time or at least that's what I tell myself