I Am The. Wife Of A 69 Yr Old Man

I am the. Wife of a 69 yr old man diagnosed with stage IV NSCLC. He is in his 5th month since diagnosis and on maintenance chemo. My son is in China, not rich, and weare poor. ,my son is a teacher. My son is scared he won't get home in time and obviously cannot fly back and forth. My husband is rapidly loosing weight, has chronic cough and sinus trouble, and sleeps about 10 to 12 hours a day. What do I tell my son about his father's time? His doctors won't say any thing.