I've got a 3 1/2 year old and an almost 6 year old.

For the first couple weeks, you'll be trying to survive. At the end of the pregnency, your wife won't be able to sleep well. I'm convinced this is training for what is to come.

After things settle down a little bit, commuting by bike may be the only chance you get to go on rides. Do it whenever possible. As things calm down a bit, life will return to (a new) normal.

Most pediatricians recommend against having anybody smaller than 12 months on a bike or in a trailer. A trailer is nice because even if the bike falls over, the trailer doesn't.

Congratulations and good luck! Oh yeah. Sleep now. A lot. Because it's going to be a while...

Cheers,
Charles