Grammar and sentence structure check [duplicate]

I'm sure more could be said about this, but I'll say something briefly so that you have a timely answer.

You can get an answer by thinking about the coordination. According to some theories of grammar (all, in my experience), in order to coordinate two phrases, they need to be of the same type (I have a somewhat technical concept of type in mind, but you probably have a good enough natural idea of what I mean). My husband's parents is a determiner phrase. You can test for this by trying to replace it with a proper name like Jack. My is not a determiner phrase (it clearly fails this test), so on this analysis, I think that you are in some trouble. Instead of my, you could use mine, since this is a determiner phrase. So I would say:

Mine and my husband Jack Millan’s parents are distant relatives and knew each other.

Or also:

My husband Jack Millan’s parents and mine are distant relatives and knew each other.

For stylistic reasons, you might want to edit it to an easier structure to parse.

Of course, you could also analyze the coordination as taking my and my husband Jak Millan's as arguments. So there might not be a good syntactic reason for preferring one over the other. But one might be generally easier or the first choice for our brains to parse, and I think my brain prefers using mine.

'My parents and those of my husband Jack Millan are distant relatives and knew each other.'

My parents and my husband’s are distant relatives and knew each other.