Family Drama

I should be so happy that my husband and I are finally expecting our first child in September but my family is stealing my joy. My oldest sister and my mother don't speak at all anymore and both have been very immature regarding my pregnancy.

My sister is saying that she won't come to my baby shower or after baby's birth if my mom is there. My mom is telling me she's coming to ultrasound appointments and then doesn't show up or call. Luckily, my husband's family is normal but I'm really disappointed in my family's behavior.

Has anyone else been through something like this? What did you do to make the drama stop?