OP, it depends who the family member is, and how close they are to you. If they had had infertility or MC or this year would they be close enough to tell you?
Not to derail your thread, and it may not even be relevant to your relatives. but we've just had DH's DSis, her DH and their new baby visit, and I didn't hold him or make much contact or attention with him. I MC in June, and my baby was due this New Year. We hadn't told everyone, so they didn't know- and i didn't want to upset her pregnancy with what happened.
Usually I'm the most baby friendly person in the room, but this year I don't want to and can't bring myself to be. I looked at him, but when I was asked if I wanted a hold, i said I'd strained my arm at the gym I go to, so I'd have to leave it for now.
If this isn't the case then I am sorry for putting this on your thread, i just wanted to say that maybe the relative has had things this year she hasn't explained, that you could misinterpret as disinterest.
I look forward to seeing my nephew properly, but am just not ready to do so yet. Sorry again, it was just a thought x