My sister wants to terminate her disabled pregnancy but her husband is against it. They asked me to be the median but Idk. Should I help or butt out

I’m torn because both of them are hurting. My sisters decision is because once they are both gone the daughter will most likely be in a facility and end up getting abused. I never thought about that before but tbh there’s been so so so many cases about this. Plus my sister doesn’t feel like she will be able to provide or be up for this and thinks she will regret having a child doesn’t think her husband is ready either. He says he is but he couldn’t even care for the neighbors dog who had a cast while house sitting. My sister had to go over and give the dog the meds. Her husbands reason is they will be a family and that’s good enough. My sister said they can try again and still build a family down the road. I’m trying to comfort both but not even sure how I could be the neutral party to both of them. I honestly feel like they need to split because they are at ends. And I think my sister needs to do what she thinks is best for her and I think her husband is wearing rose gold lenses as he does for everything then ends up backing out. Haven’t told them that