Facebook sharing.. how to fix this?

My husband doesn't use social media much but when he does, he shares my posts (usually about the kids or something similar). We just had a baby and he shared my post but I realized that only our mutual friends see his shared posts. Is this a setting on my end or his? And no, if it's on his side it's definitely unintentional. He's just not Facebook savvy and neither am I.

Any idea how to change this? On the rare occasions he posts himself there are no issues.