Pregnant with baby number 3 afraid to tell family

So i just found out Im pregnant and Im not sure how to tell my family. My mom has always said 2 is enough and has made several comments about how i should just be done with 2 because thats the “perfect family” Also my son has a birth defect and she thinks i shouldnt have anymore. I really want 3 kids and this was planned and im very excited and happy. I just know once i share the news with her she wont give me the reaction i wish for and will make me sad. Iv been hinting for a while that i want 3 kids. She blames it on my husband, she for some reason thinks he is the one putting 3 kids on me bc he came from a large family; when in reality i was the one who talked my husband into 3 kids.

How would you tell her and the rest of my family? should i tell them separately or all together?

When would be a good time to tell? I would wait as long as possible BUT my last pregnancy i told her and wanted to wait to tell some other more distant family and she said shed be mad if i kept a secret from her as long as i did from other family members, so i feel sooner is best.