Nothing wrong with asking how the father is doing but the reasoning behind it is confusing. How do you appear callous to your friends? How would they even know what you ask your husband? They are not omnipotent mind readers. My or my husbands friends wouldn’t know if I ask him this or that. Even my very best friend doesn’t know what I tell or ask my husband. Even if you ask how his father is doing he could still tell your friends that you didn’t ask.
I think if you want to maintain good friendships you should ask how their parents are doing and be good friends for them, I don’t see how asking your husband questions ensures that they keep you as a friend. It’s not their business what you talk to him about.