I have found it is best to remain low-key with my disagreements about faith and politics with family members who don’t share my core values. They are a minority in my family firmly stuck in a leftists world of academia and agnosticism, but my home and table are a testament to my faith and values. They return every year, they do not seek conflict over faith or politics (they are very polite), and we have a nice time.
I believe my family/home is the best reflection of what I believe. I also believe the testimony of our lives and those of our family is a positive influence. I would firmly and politely put an end to any nastiness if that were an issue.
Amazing what happens when you call for prayer before dinner. Then talk about what the church is doing with missions.