First I will give some background on myself and my relationship.

Im 21 yrs old.
Im not "technically" a step mom. However, I have been with my bf for 3 1/2 yrs now. We met when we were 13/14 yrs old in high school in Florida. We had a "thing" back then. he was my first in everything.... But we stayed best friends. I moved back to CT a few yrs later, he moved to Ohio in 2006. Once he moved there we ended up getting together (LONG story lol). I moved out to Ohio a month after we got together then we moved back to CT 6 months later. We have a 2 1/2 yr old daughter together and are expecting our 2nd daughter this April. (1st one was a surprise, 2nd was planned.) We are not married yet because of finances and we want it to be very special with our daughters involved in the wedding.
Now to the other part of this:
He has a soon to be 4 yr old daughter with his ex. He was physically involved in her life for the first 4 months. (his ex stayed in Florida with his daughter when he moved to Ohio, then they split and he got together with me.) It has been impossible for him to be involved in his daughters life physically because of the distance. The cost of plane tickets and hotel stays are outrageous. He hasnt talked on the phone with his daughter either because she was too young at first, then he got scared. Scared because he didnt want to confuse or hurt her more. He felt like by talking to her on the phone she would be more hurt because she cant actually see him. We have stayed in contact with his ex through emails though and we have sent birthday and Christmas presents to his daughter.
Background on his ex: She tried her hardest to split us up in the beginning. She would constantly call saying it was about his daughter but she wouldnt say a word about her. Just about the relationship the two of them had together. She would send nasty emails to me also. She is with guy after guy. And she does have her daughter call them "daddy". Which my bf feels like that just confuses her even more. She was barely involved in her own daughters life for the first few years. She would move to different states with her friends while her daughter stayed with her grandparents. However she just got her own place and her daughter now lives with her 24/7 (as far as we know.)

Well, my bf has been contemplating whether or not to start calling his daughter. Which I dont have a problem with him talking to her because she is completely innocent in this whole thing. Then last night his ex sends him an email :

" why did you leave the way you did im trying to be the best mother i can to tessa i just got us our own place and everytime she ask about you and if she can see you and talk to you because she cant she hates me for it everytime thanks alot for making her hate the one and only person who has been there for her i want you to sign off of her im looking into it this week your a shitty ass dad to her and you dont give two shits about her if you did you would do more then wat you do for her. shes misserable and i dont know what to do i could use some advice or something please your suppose to be her father."

He hasnt responded to her yet, but he says he will be calling his daughter today. Here are my feelings on this whole thing:

1. I am scared. Ive never met his daughter in person or heard her on the phone. And we have made our own family together. Now after 3 1/2 yrs he is going to bring her into our family....
2. I feel jealous for Our daughter. Even though she doesnt understand whats going on, I feel jealous for her. I hope someone understands that.
3. I myself feel jealous because this is his "first" child. I know that is wrong, but its just how I feel. And I came into this relationship knowing he had a daughter but he made it this way (where she wasnt involved until now.)
4. Im stressing out, already went into preterm labor once a few weeks ago, and when I read her email and he said he was going to call, I started stressing like crazy and started having contractions. I calmed down enough though to have them stop. (Im 33 weeks pregnant)
5. His ex caused ALOT of problems in my first pregnancy. She pretty much ruined it. All I can remember of being pregnant with our 2 1/2 yr old is all the things she did, emails she sent, messages she left on our phone, etc.... Now this.
6. Confused on what I should say or do. Whats my role? I dont want him to have two separate families. If she were to be involved in our lives I would like it to be one whole family. Not : Phillip and Tessa (his daughter)... then.... Phillip, Marlene(me) Lily(our Daughter) and Alessandra (our baby)

Theres probably ALOT more and I could have typed all this out better but Im so confused right now. Thanks for reading. And to make it clear, I dont hate his other daughter, I just dont know her. And I dont know how to make this transition while we are making another one in just a month (having our 2nd child.).

Also : I have an almost 4 yr old half sister. My mom got pregnant by someone that ended up leaving and never meeting my little sister. However in her situation we all feel its best for her not to have her father around. He lives in another state, and if he ever was to be involved, it wouldnt be a constant thing. It would be phone calls and a visit once in a blue moon.