My Dp andhis ex have a particularly unpleasant relationship, and unfortunately this has caused a great deal of tension between everyone.
Although we found out through the grapevine that his XW knew about my pregnancy, we didn't tell them til a little later - maybe 25weeks or so?
Her response "Oh - whos the father". hmmmm. It wasn't nice at all. I sent photos when she was born, and we have sent letters, and all the cards come from jenna too, but for months we didn't get much love from the stepchildren.
Then we happened to see Sam out and about at netball one day, and she got a cuddle with her, and after that we started getting letters from her about every month?
She sent one saying how much she hated jenna when she was born, but she realises thats not jenna's fault so she got over it.
She came over for Jenna's birthday party on Friday, and had a lovely time. I truly believe she just sat and soaked up all Shane's family as it had been such a long time since she's been to a family thing. When she left, she was nearly in tears - it was very moving, and I think she will be in to see us a lot more now.

I'm not sure when to tell her about this baby. I guess I'll wait til I'm well on the way specially after the recent m/c, but I'm not sure there is anything right or wrong you can do.

I think just continue to love the stepdaughter, and realise that no matter what you say or do, there will be some repercussions and unpleasantness, but eventually she will come around. You dont find many teenage girls that dont LOVE babies. Most importantly, make sure that your relationship with your DP stays the strongest. You are both very important too, as is this little baby, and they are your main family.

Best wishes for you.
Fi