What to call EM in the years after baby is born?

Karen1024

DD is 5 months old and I've been thinking about how I want to refer to her birth mother as she grows older. We're in an open adoption and will be seeing her a couple of times a year.  So far, things are going pretty well! It's only been 6 months, but nothing is really feeling "natural". To make it more complicated DD has a full sister and right now we just refer to them as sisters.  Unfortunately, we worry about DD's sister growing up as her mother doesn't have many good parenting skills and she has terrible habits and no boundaries.  They live 2 hours away and we don't anticipate being close like family, limiting the visits to twice a year unless something major changes.

I still sometimes refer to her as DD's "Mom" but I don't like it when I say this because I think to myself, "I'm her mom!!" I feel like a traitor to myself which is miserable! I'm not babysitting, it's my title. She doesn't have two moms. We're not equal partners.  She has a special status I want to acknowledge, but I don't have a word for it! 

I think "Birth mother" or "Biological Mother" just sounds weird.  Maybe I just need to get used to it? As in, "Hey ___, we're going to see your sister and birth mother on Saturday." We could just call her by her first name, but that doesn't acknowledge her special status. Now that I wrote all this out maybe Birth Mother is okay. It's just some EMs seem not to like it prior to delivery but we're past this stage now so maybe its okay?