I need to know if I should extend an invitation to my SIL, and her family, for DS's 2nd birthday party.
My H and his sister have not been speaking to each other for a few months now, and with DS's birthday around the corner I'm not sure what I should do. She is pissed that he deleted her and her kids off our Facebook accounts. Her daughter shared one of my photos of SS from DS's party last year with BM and BM's sister. It was then used by BM to blast us on fb. It was BAD. We have BM blocked, so we didn't know until multiple people from town came and asked us about what she was saying. A person even threatened to beat us up.
Anyways, it wasn't my SIL's fault her daughter made a bad decision, and I am sad that she is not speaking with us still. However, I don't know if H's niece will come and take pictures then send them to BM/BM's sister. I am also afraid if I don't invite them it will cause even more animosity.
So do I invite them, or do I leave them out? I'd like to invite them, but my H isn't sure about it. We really don't want anyone stirring the BM pot.

Re: To invite or not to invite?
Personally, I would stay out of it.
I do think it is ok to have a policy that you will not FB friend anyone who is friends with BM, since you do not want her to have access to your lives.
Did Niece send the photo to BM, or just post it on her FB page, where BM got ahold of it? If it is the latter, your H is blowing things way out of proportion. It's ok to ask niece / SIL / family not to post photos of SS, but for him to GO INTO your FB account and delete people is not cool. He should have acted like an adult and had the difficult conversation with them.
If someone is not speaking to you, I would not invite them to your family party. It is just too awkward, and the first meeting should not be at a big group event.