I had to come back to this thread after seeing my sister last night. My sister's getting married in a couple months and last night was her bridal shower. I was almost surprised (but knowing my sister, not too surprised) how easily she calls EVERYONE "Mom". She of corse calls our mom "Mom", she calls my M-I-L "Mom", she calls her future M-I-L "Mom", and she calls her future step M-I-L "Mom". Last night was getting a little confusing with so many of her "moms" in the same room, she had to call all of them "Mom" followed by their last name.