Bitter baby mamas and child support 🤦🏼‍♀️

Ana

So me and my husband have been married for about 3 months now and his baby mama has been so bitter since the beginning of our relationship. It's not like they were together that long or they even had something going on and off she just had his baby when they were teenagers. So his son is now 14 years old and she's upset because I had him block her. Am I wrong for that because every time she calls him or texts him it's not about his son it ends up being about me and he gets super uncomfortable and it also makes me very uncomfortable. I'm the kind of girl to react now talk about it later and as much as I want to rip her tongue out I look at her son and I see his hurt because she can't act her age (29). Now she went to child support and filed for partial custody. So I'm just trying to get a little understanding of the guidelines in PA with child support since we are married. Are my children considered his since we are married, obviously I know they're not physically his, but I mean financially and am I allowed to sit in on the hearing?