I agree - is there any way for your in-laws to come to Canada? They don't have a baby to tote!

As far as the fighting/arguing goes - can you and your DH take a little time away to relax and become closer? Or maybe try to have some regular dates? My DH and I have also had some more arguments than normal lately, and I think it is because we are both tired and very busy, and we end up being frustrated with each other. Otherwise, maybe you could go through a good book for couples together or something like that. Ken Sande has a great book called The Peacemaker, which I am thinking of reading with DH.
Anyways, I hope you are able to come to a good solution for all of you. Stress in the family is soooooo exhausting!