Last month, I asked my mom what they were doing for Thanksgiving, they were going out of town to see my brother. My wife was working all day, and my son was going to see family. So I told a co worker I would work for them so they could enjoy the holiday with their family. Now my parents change their plans and staying at home, my wife’s schedule changed to the morning shift. The co worker was on vacation and had a family member pass away. They spent almost entire vacation dealing the funeral, family, and the loss. The question is do I see my family or do I still give the holiday to the co worker so they can at least have a day of joy in a time of despair?

You give the holiday to your co-worker! It’s not their fault that your parents changed their minds! It’s not their fault your wife’s schedule changed! It’s not their fault the experienced a tragedy.
Since you planned on working for them anyway, it would be good on your part to work for them. Might give them the option and call and explain your situation as well. You never know till you ask.
Have thanksgiving dinner with your wife and parents. There’s no sense giving it away, the co-worker will be sad about his loss anyways, so he might as well be busy at work.
You are a wonderful man, what a nice gesture on your part. Unfortunately you did commit to your co-worker and as hard as that may be to not be with your parents, you should still give your pain stricken co-worker the holiday. Reading of your generosity I’m sure your parents will understand. As the saying goes, “The apple doesn’t fall Far from the tree”, your parents will understand.
Make the best of your Thanksgiving.
Good luck to a good man.
Hope ♥