It makes sense to try to get the mucus coughed out. But it's hard work for both of you. When mother-in-law got bronchitis/pneumonia in nursing care, they gave her breathing treatments for the purpose of breaking up the mucus so she could cough it out. It's dreadful for the older people to have to do that, when they're already so weak, most of the time. But it's the only way I know of. Good luck!