I haven't done it but there are options in the privacy settings to block individuals or groups of people from seeing your posts.
I think you'll be able to create a group called "family," and then change the privacy settings for that group so they can't see your posts. Also, I think there's an option when you make posts that you can make them viewable to only certain groups, too.
Again, I haven't done it.. but I know it can be done. Google will probably be more help. Or click the "?" help box up on the right top corner and read through the privacy help topics. It may explain it right there.
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No

for supporting trump. Because doing so is deplorable.