Need suggestion with good herbal concoction to bust immune system for sick elder.

HI Everyone,

Over the past month I have been posting messages to gather information that could aid me in helping my grandma improve and maybe reduce/eliminate a meningioma her Dr recently found. Right now she is stable, but her body is very weak and recently developed a cough and flu that has lasted now for 2 week.
Can anyone help with suggesting a good mixture of herbs that can help bust the immune system?. I'd like to order a good bunch of herbs that she could take everyday in teas that could help her immune deal with common bacteria or viruses. Please, any suggestion will be like always greatly appreciated


Thanks so much,

Fran