I can't tell from your post if your husband blew up this morning & made the comments about your familly, or if this has been an on-going communication from him to you.
If the first - then just take a deep breath & let it go. He is going through a lot emotionally, especially today as he leaves to care for his mom (sounds like the only family he has left, & she isn't 100% "there"). Additionally, you are going through a pregnancy & might have a different perception of his comments than you would have if you weren't going through so many changes.
But, if this is just a repeat of a pattern (more than a few months) then I would suggest approaching it with him. Be compassionate & understanding that he is going through a lot - losing a sister & now facing losing his mother, that's a lot to bear emotionally.
And men don't always get in touch with where they are emotionally & recognize how it affects them until they start lashing out. Find a time to talk when the emotion is not raw, and approach it from the perspective of knowing that he is going through a lot, & he has a right to feel the way he does, but you are asking that he express it in a way that doesn't hurt you in the process.
Because we can't make people change the way they feel, and right now, whether you like it or not, his feelings are that he is feeling the universe dealt him an unfair hand. He is losing his family, and whether you have one person you are close with or 20, he feels you have a better situation that he does.
By saying all this, I'm not "taking sides" & I don't want to minimize YOUR feelings about what's going on. Because they are just as valid. So don't fall into the trap of trying to point out who is right or wrong in the way they are communicating, feeling & expressing their feelings. Instead, acknowledge that he is going through something that is difficult for him, & he has some emotional turmoil. Let him know you are there for him, (& if it's true, that your family is as well) and ask him to help you by expressing his pain in a way that doesn't hurt you.
If he is open to it, you might want to suggest that he see a grief counselor. Someone that can help him recognize the emotions he is dealing with having lost his sister & facing losing his mom, & help him to validate his feelings & process them in a way that isn't toxic to him & his relationship with others. If his mother is in the hospital, there is usually someone there family members can meet with, also your local church clergy.
And really, the loss of his family members affects you as well, so if you are experiencing turmoil at the thought of how to deal with his mothers illness, or you need help understanding & communicating with your husband, don't be afraid to reach out to such a counselor on your own.
I will be praying that when your husband returns home you can both reconnect in a positive way, & move forward together. T.