Babymama Drama

My s/o has a child from previous relation whom lives in a different state then us. He used to be able to see his child on the weekends but ever since he's been with me (2 years) his babymama won't let him see the kid, the only way is if it's at his moms or grandmoms house, she won't let her come to my house not unless she is there too... She says she's not comfortable, when I have already met the child once I know she's just jealous to say take the child shopping and it will just be them 3 together. I'm so fed up with the shits it pulls me away from him. Idk what to do anymore