N.L.
Can definitely relate. I am also pregnant with our 2nd baby, our first is currently 14 months old. She loves her daddy, but any need she has or dicomfort or anything she insists on coming to me and not letting daddy do it (whether it's putting her to bed, feeding her solids or her bottle, etc.). But the thing is- I understand our daughter more, I read to her (she is a bookWORM), I'm more patient with her and so forth. I don't think it's some biological mystery- it's that babies are "programmed" to survive and they learn quickly who meets their needs and how. I'm also the one that gets up in the wee hours if she needs something.
My point is- it really isnt so mysterious and un-reachable to change the dynamics. No, men can never be a 2nd mommy, but they can take the time to read that same book for the 7th time in a row, take the baby in the other room if need be in order to feed him/her as the only choice they have, etc. And these are the things we are working on in our parenting. I am also a F/T working mom and now tending to this pregnancy also so we are having big talks about how these things need to change in our household. I suggest your husband & you have some real talks about it. You obviously know your son so think about what it is that builds love and bonding times between you & have your husband start there (i.e. is it playing with animals and imitating their noises, trains, etc) then move on to the need type stuff. And honestly, you may need to "dissapear" such as going to a remote room (and DON'T go rescue) or go take a wal/run an errand. If you are both consistent with it, the dynamic will definitely change b/c your son's understanding of how he can make it in this world will be broadened. Best wishes, N.
PS It has definitely been working for us. Not totally there yet, but absolutely a note-able difference in how much she resists her dad's help. And the irony of it all, then our newborns will come and we'll be so focused on meeting his/her needs that it's almost guaranteed that the dynamic will shift yet again to the opposite pole. And then we'll once again work on re-balancing it. Law of the land I guess.