Venting/ Advice

My boyfriend and I have been together for 4 years and we have a 2 year old and currently pregnant with our second child. Since the beginning his family has always talked down on me negatively & judged me without actually getting to know me his mom especially. He’s the youngest child so I always thought that was the reason. I’ve tried going around them & making an effort but that didn’t work. When I was pregnant with our first child his sister told him to get a DNA test because in her words “a child is a big responsibility and she didn’t mean it as I was sleeping around”. Our relationship did get serious fast but it came naturally . After our first was born his family never made an effort to come see her unless we went to his mom’s house for his family to see our daughter. I’ve never felt welcomed or comfortable around his family. They only live an hour away from us but never come to any events we give unless it’s in the city they live in. After our daughter was born I had terrible PPD and his family made it worse with their judgment & no support. He would randomly insist on going over there for them to see our daughter because my family does. My family has always welcomed him, respects any boundaries we have when it comes to our child, Supports us the best they can. I tried telling him how I felt but he presses the issue for us to go around his family more. Our daughter has autism and because of comments his mom made in the past about her development I don’t feel comfortable with our daughter going around them without me. This has caused prolonged arguments constantly in the past because he thinks I should over look all the things his family has said about me over the years. With me being pregnant with our second child I want to be stress free and try my best to avoid the conversation but he keeps bringing it up.