Should I (29F) bring up my worries to my sister (29F) about her husband (26M)?

I need advice about my sister and her husband, who we can call Jake. My sister and Jake have been together for 7ish years, they have a 4 year old daughter, and he has a daughter he had in high school with another woman who is 9.

Jake doesn’t work and hasn’t since a few months after he moved into my sister’s house (which was like 2 months after they started dating.) He has some sort of chronic illness/disability that I don’t know all of the details about, but as far as I know, is a real struggle for him. However on top of not working, he also does nothing around their house. Cooks no meals, cleans absolutely nothing, doesn’t drive, no yard work, the list really goes on. As far as I’m aware, his only task is cleaning their various litter boxes.

My sister works full time, and goes to nursing school 3 evenings a week directly after work for 5+ hours, and every other weekend for 16 hours. Their daughter is watched my me (for free) and has been since she was born. Usually every day of the week + some evenings now that my sister’s in school. So my niece at my house 6:30am-5:30ish pm, but sometimes up to 10pm, through the week, and sometimes on the weekends. Jake very rarely is the one caring for her, though he does sometimes do the evenings when my sister is at school. If I’m not available, and he’s not available, she goes to my parents’ house, which is directly nextdoor to my sister’s house.

Now I am also chronically ill/a stay at home mom, and I aim to be understanding about the limitations his body places on him. He says he cannot work and I try to take him for his word. He also cannot apparently do anything around the house (which I also try to understand, but it’s difficult). Though he manages to go on 1-2 hour walks with their dog daily, so I feel like he could maybe sweep a floor every now and again. But I digress.

My sister struggles financially exceedingly because though she went to school and loves her career, she makes < $17/hr and is the sole income for the household. Her husband sleeps most days until 12-1pm and stays up all night playing video games while she does quite literally everything their life requires. She also takes care of her stepdaughter by herself on the weekends they have her, and often times Jake doesn’t even come downstairs once he’s awake because he plays video games in their bedroom instead. I have even witnessed him standing in front of clean, unfolded laundry in a basket while he waited for her to dig through it and give him a shirt to put on, while she was trying to cook dinner, it’s really that bad.

Now, my parents despise Jake. Hate him. My mom however makes this extremely known. She’s several times made comments to my sister about Jake over the years (which my sister takes poorly). And when she has to be around him (which is very rarely because he does not leave the house or go to their house ever), my mom literally ignores him even if he’s speaking to her. My mom has always been a pretty big asshole so this isn’t surprising to me (and was an abusive alcoholic our entire childhoods, though has been sober for about 10 years.) Anyway, y dad on the other hand is cordial, and I only know his feelings about Jake because he’s told me privately. In turn, Jake hates my mom but doesn’t have a problem with my dad.

Jake’s own mother was a horrible person and he genuinely had a rough childhood (I know his family a bit so that’s confirmed), and he cut her and all his siblings out of his life a few years ago. So he has no family, and also no friends. My sister also has no friends, and the only people she has outside of him and their kids are me, and our parents.

Now, while they were on vacation recently, my dad was renovating their bathroom, and my mom was there helping/taking care of their dog. According to Jake, a lot of his stuff in their room was all in different spots than how it was, making him think my mom (and if it was someone, it was her not my dad) went through their room and things. An obvious, weird, invasive thing to do. Boundary breaking and not acceptable. So he wants my sister to cut off our mom, especially from their daughter. He wants their daughter completely removed from my mom’s life, no visits, no speaking, nothing. He told my sister his mental health cannot handle our mom being in my sister and their daughter’s lives anymore, and he can’t stand being in the house next door, and need to move (which my sister cannot afford to do.)

She came to me crying this morning because she wants to support her husband, but doesn’t want to cut my niece off from her only grandparents, only family, and the only support she personally gets outside of me. And she doesn’t know what to do.

My big problem is that I have personally seen him treat her horribly. I’ve been over to their house and sat in the living room while he screamed abuses at her in the other room with music blasting over it, while I sat with the kids trying to keep them out of it. My niece has told me similar stories, and fucked up things he’s said to her/in front of her (threatening suicide and other things). And remember, she’s 4. I’ve never wanted to bring this up with my sister because she reacts poorly to criticism of him, and he loves cutting people out of his life, and I’ve always been worried he’ll try that with me. My sister makes every excuse for him. His childhood. His mental health. His chronic illness. Nothing is ever his fault and he can’t ever help it, whatever it is.

Before her husband, she was in a long-term relationship with an extremely emotionally abusive man and she was the same way with him. These have been her only two real relationships. It seems clear to me that she picks these men because of childhood trauma and low self esteem, and doesn’t think she deserves better. Side note, my parents also hated that guy (and so did I), and so now she will also be like “mom just hates anyone I bring around”, and uses that as an excuse too, Though, despite my mom’s many issues, I think she’s been genuinely worried about her in both relationships.

I can understand Jake being fed up with my mom because I’ve lived with her frustrating behaviors for years. But he doesn’t seem to care that cutting off one of sister’s only supports will put even more on her shoulders, and isolate his child and his wife. To make matters worse he’s gunning for them moving across the country in a few years where they know no one (and completely on her dime), and I really worry about her and my niece being physically alone and emotionally isolated from everyone but me in that situation.

I’ve given her my two cents about considering her needs as well, and not just his, and pushed her to consider conflict resolution with my mom about it, something that makes Jake feels respected, if my mom can genuinely apologize and change her behavior, without cutting my sister off from her supports. But if he doesn’t go for it, I worry she’ll give in and do whatever he wants her to do.

I just don’t know if I should make known my worries about his behavior and how she’s being treated. I am worried about her and don’t like this new push from him to cut off her family, especially when he treats her that way, and everything’s on her shoulders. But I’m worried that it will backfire and she’ll end up even more isolated, from my parents and from me. But I’m also worried about not speaking up when I have a chance. Feel caught between a rock and a hard place.

TLDR: my sister is married to a man who contributes almost nothing to their household or parenting, but who’s behavior worries me, and he wants her to cut off nearly all of the already very small support network she has outside of their household. need advice on how to approach the situation. Should I bring up my concerns to her, or hold my tongue?