Does "Family" have to be related to you ?

All families have "different" relationships and situations that develop out of "the normal" patterns of life.  I always find it fascinating to hear how real life is often more complicated, and far less believable, than any soap opera or dramatic TV show.  Here's a glimpse into my "extended" family and a situation that at least I find a little odd:

Today I found out that a used-to-be-sister-in-law is now expecting (see: pregnant) again with her new husband.  My niece and nephew will be having a new half-brother or half-sister (way too early to tell which yet).  Not that unique yet I know ... but stick with me here.  That child will have no direct relation to my children because it is my wife's brother's ex-wife's child.  Feel free to get a pen and a piece of paper and draw a chart.  I'll wait.

Okay, glad you made it back.  Sorry for making you do homework.

Now, another of my in-laws is still legally married to his first wife, but they have been "separated" for many, many years now.  He has a girlfriend who had a beautiful baby boy last summer (it was not his baby -- the father is actually her legal husband, but they have been "separated" for a while now too).  That child also has no direct relation to my children but we still refer to him as their "cousin."  And I think it is the right thing to do, because of their current relationship (and because he is just adorable and his mom is really sweet and seems to be making my wife's brother very happy!)

So ... am I thinking about this the wrong way?  Should I just accept either child as a nephew or niece?  Or is it okay to base their "relationship to my family" on their current relationship with members of my extended family?

If that is not "unique" enough for you then just wait'll I tell you the story about the brother who married the daughter of the man that I verbally berated during a church basketball game.  Or the one about another brother who married his (get your pen and paper back out) older brother's ex-girlfriend's oldest daughter.  There are just so many stories ... and, apparently, so many "cousins" !

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