My husband wants me to cosign a home loan

to help his younger sibling to get approved for the loan and buy a house for her to live in. Our house is already paid for. I was okay with him co-signing by himself but now he wants me to also be a co- borrower so my income will be included and they will be able to get approved for more. Is the risk about the same whether I’m a co-borrower individually or the wife of a co-borrower?