Wtf do I do

My boyfriend & I have an 8 month old. He cheated in February 2024. (Yup I know I’m stupid for staying with him.. but I just wanted to be a family.)

I notice the girl has a new baby in her profile pic. I ask him if he used protection, he said he did. Then I questioned why she has a new baby in her pic, if it could possibly be his. He swears he used protection. If it is his, baby would be around 2 months old. She has me blocked bcuz I reached out in 2024 confirming if she slept with him. She explained, apologized & now blocked me. Prob bcuz I reached out to her twice.

What do I do? Do I have him reach out to her? Do I just ignore the possibility that it could be his? I know most of y’all are gonna say leave, but idk.