Husbands working situation (2)

Hi Brooke, this is the second part: I have a hard time figuring out, how to deal with my husbands working situation meaning how to help him to clear his mind about it and find new ways to think about it.
(2) The other thing is, that one of his colleagues at another department, with whom he has to work with, is apparently not so smart. He doesn´t understand some of his things he has to work on and quite often, he asks my husband for help. But it´s not my husbands job to help him (there is someone else for that) and he doesn´t have the time to do so, because he has a lot to do already. And also my husband dislikes him for being braggy and cheeky even though he is new and doesn´t do his job properly. How could he deal with this situation and change his thinking about this colleague? I would love to hear some of your ideas. Thanks in advance!