I would definitely talk to the pediatrician. First thing you need to know is how is his vision and hearing. Does he like to be touched and held, when he smiles, is he actually smiling at you or is it unintentional.
Does he show interest in playing with you (ex, "peek a boo")? Does he recognize family members (by smiling when mom/dad enter the room)? I wouldn't worry about laughing b/c it depends on child's temperament. My daughter was a serious baby and rarely laughed.
I don't have children but maybe go on the Child Behavior Forum. Ask your question there and someone might have something to say. Sorry I couldn't do anything more for you. The only thing I can say is that I work at a daycare and there is a boy there that has just turned two this summer. He has been at our daycare since 15 months and he is just now starting to try and say words and communicate. I guess his brother was very late in all of that too. Keep hope, talk to him and communicate with him as much as you can.
Yes, spoke with pediatrician and they are on the wait and see approach. I just wondered if anyone else had a similar experience. Thanks
Have you asked your doctor or pediatrician? I would ask them and see if they are concerned. Good luck.