Although I know how much my son loves his family he does not include us in holiday get togethers. He puts his in-laws first and leaves us waiting at the end of the line. We want to be involved in his life as much as his inlaws.

Have you mentioned this to him?
Do your family have a good relationship with your sons wife?
Is he the one inviting over his in-laws or is it his wife who is in charge with inviting guest?

It's all about balance.

Why not plan the next event at your house, well in advance. Let them know that they are invited, along with your daughter-in-laws family too if they wish to come.

Have a big shebang barbecue for a birthday for example. Maybe your son's?

Another thing you might try is before, dare I say it, Christmas is on the horizon, again, well in advance, even September, suggest to your son and his wife over dinner at your place, that you'd love to have them agree to coming to your house for the holiday.

It's important that you invite them both. Putting pressure on him as an obligation he has to explain to his wife, will only build resentment.

Tell them that, although you understand obligations to both families can be a tug of war sometimes, maybe they could agree to every other holiday at your place.

Maybe you just have to go in the backdoor on this one, in a positive way, without any resentment, but just straightforward thinking to please everybody.

There's really no excuse for that, unless you live a great distance away from him and his in-laws live relatively close. Talk to your son about alternating holidays with the respective families (or even joint celebrations) without accusing or putting him on the defensive.

He might be overcompensating while trying to prove to his in-laws that he's a member of their family. I would just talk to him, if you haven't already, and try to find a balance. It sounds like he's a newlywed, so balance should come with time.

Does he know how you feel? How can he change if you don't tell him your concern?

It's not easy to divide 50/50 exactly. But should suggest to him that he spend more time with your family.

Please call your son and discuss this issue with him. To be frank he may not be doing this intentionally. He definitely cannot be doing this to hurt you. All you need to do is to discuss this with him so as to know his mind.