<human>: Can you give me the gist of the text in a nutshell?

I have a three year old son who spends a lot of time with my in-laws. I love them both, but my FIL and his best friend regularly make comments disparaging Blacks and gay people, using offensive words and all. (We are all White.)

I've spoken up about it, telling them that it is offensive and cruel. Each time I've seen shame flash across their faces, but the comments haven't stopped. 

After having the "this is wrong" conversation a few times I just walk away from the conversation now - noticeably. They've called after me a few times, even commenting that they must have offended me. I know for a fact that it offends my MIL and other people - you can see the discomfort on their faces. But this is the south and they are baby boomers. I think their childhood environments were pretty rife with racism and homophobia. 

I've said my piece and FIL and best friend know how I feel. I've spoken to my MIL (his wife) about my concern that my son will pick up these behaviors, but my MIL just says with a sigh, "That's how they are. just ignore them."

But my son is getting older. He's asking more questions, picking up new words and phrases and, like any kid would, looks up to his grandfather and other loved ones (my FILs best friend is like an uncle to my son.) How do I make it clear that they should NEVER speak like that in front of my son? Should I even try? Should I just teach my son that some people are bigots, including his grandfather?
<bot>: My FIL and his friend sometimes say racist and homophobic things around my three year old son and I refuse to allow him to grow up thinking this is normal. How do I approach the situation?