Wow-my family seems so normal now.  That's nice. 
Except for my husbands brother and family.  They live in the same city as us - yet we see them only on Christmas.  They are invited to all the usual family fuctions but never come.
They used to though - until The Incident.  My youngest and their youngest (who is actually a few months older) were playing around at a brunch years ago at some buffet restaraunt.  They were all of 2 years old and my husband's brother jokingly (?) egged his son on to hit mine or wrestle with him or something.  Nothing much happened - a quick few tears that ended.  I missed the whole thing but was curious - so the next day I emailed her asking what had happened.  And apparently while describing the incident in a way very similar to how I just did, I angered her to the point where she sent several flaming emails my way.  I replied with an - oh no - you've misunderstood - I didn't mean that.  This furhter insulted her, implying that (gasp!) she'd not understood what I was trying to say.
So - out of an incident 6 years ago, we don't see them anymore.   I'd love to get to know my nephews more - but I think they fear her wackiness as much as the rest of us.
She's taking medication now (mental issues) and that's helped a bit.  Apparently I just got a taste.
But still - we only see them once a year.
On my side of the family is the child molesting husband adopted child of a relative who - thankfully - is now dead.  So is his married-to-someone-who-could-never-do-that wife.  Their child is with other family members.