Another vote for proper legal advice. Your OP kind of suggests you are not fully supportive of your son, if I am wrong I would recommend you do everything possible to ensure he has a stable safe environment to live in so there is no good reason for a court to deny access.
There is a clear process to go through to get access to his son. As long as he is the legally acknowledged dad.
Don't get despondent, keep strong as a familly, support each other. Don't accept a no to access or take any nonsense from the mother or her familly. The child is 11 months so it doesnt need breast feeding any more, so there shouldn't be any reason to deny proper access. Insist on proper unsupervised access.
Good Luck.