How to tell my mother and MIL they won't see our baby?

Please no religious advice.

My mother is a terrible person and was an abusive mother as well. However, I'm sure she still expects to see her grandchild sometime when they are born. This isn't happening, ever. But I still feel for the pain she will experience from this, and want to tell her kindly. To make matters worse, my dad died last month (he was a great man) and he left his life insurance to my mother and I. However, he only did that verbally. Legally, the money is only hers. She is planning on giving 'what she has decided' (her words) to give to me in February, and if she does everything will be okay, but she is acting like she wants to withhold the money my dad left me (I am disabled and can't work, my dad was setting aside for my future) longer than that. As in, she wants to give me a small amount every year instead to avoid taxes, when I will gladly pay any tax to get my money away from her. My point is, what do I do if she doesn't give me the money in february? I can't hide my pregnancy when I see her in March (I have a hearing for my disability case) and if she finds out like that I worry about the money. I can't stress enough how much we need the money, so just forgetting it is not an option.

In addition, my mother in law is unfortunately similar. She was negligent and emotionally abusive to my husband while he was growing up, and we don't want her in our child's life either. She even had another chance to redeem herself recently---she was taking care of someone's child for them for a while---and she smoked in the home daily, did'nt discipline the child for purposely hurting a dog, and a few more things I wholeheartedly disapprove of . She's proven that she cannot be left alone with our kids, and I already know how she would treat them emotionally and I don't want my kids to be damaged by her like my husband was. How do we tell her compassionately as well? She will be more surprised because she acts like she's never done a wrong thing in her life, and I know it will make life hard as well because she will blast us to his grandma, one of his only relatives. My mother in law can be very malicious, manipulative, and guilting, while still somehow making people outside the argument feel pity for her.

Cutting our moms off like this is the hardest thing we've ever had to do in our lives besides go through my father's death, and we wish we could give them a chance, but we also know that we cant for the sake of our child, and our child is our only priority now. Any advice welcome!