Acquaintance ignores me on FB after she friends me... what's the etiquette?

[Heidi]

As far as I can tell, you have no obligation to this girl whatsoever. Just forget about it.

If it's important to your friend, or the son, then you might choose to be the better person and be civil. Or just explain that the girl wasn't interacting with you, and you prefer to only keep "close friends" on your list.

You really haven't done anything wrong... though you could have been a little more tolerant about her "inane" posts about her life. Just sayin'! But it's totally annoying when people add you and then ignore you. Perhaps she was hoping to add more people to her children's birthday party lists.