When I first went to my MW when pregnant - she said, "From this point on, don't read any books and don't google anything".
So, I haven't
This site is the only one I have gone to as it is real life experience.
My LO (just over 3 months) never goes to bed before 10:30 or 11:00 pm unless she's really exhausted and she doesn't nap more than one hour at a time during the day. She's done this since about 2 weeks. We were really worried as everyone kept telling us that babies should sleep 18-20 hours a day. Ya, right... We just decided that she wasn't one of them and she wanted to be up. She also likes to just lay and talk but she's totally relaxed. So, we figured, she'd sleep when she wanted to.
Personally, I don't let her cry more than 10-15 minutes. I'm not a big fan of the let them cry philosophy but that's more me and I can't let it happen - every thing in me says to do something if she cries for longer.
If it isn't hunger, wet diaper, etc then I do the standing over the crib and talking and rubbing her cheek etc. if it is soft cries but if it is hard cries I just pick her up and walk with her doing the shushing sound... If that doesn't work then we go to the rocker and if that doesn't work - daddy takes a turn...and so on.
I'd just see how it goes and maybe let him stay up a bit longer and see if that helps...
Good luck!!