My grandmother, aged 84, is currently in the hospital, recovering from an emergency appendectomy and a resulting minor infection. 
Apparently, she wasn’t feeling great a few days ago. At first she thought she’d just pulled an abdomenal muscle while working in her garden (Yep, she’s 84 and does activities which could lead to pulled muscles), but it got progressively worse. My aunt took her to the hospital, got her checked out, and they found a mass in her abdomen, which apparently means “surgery, now.”
What they found: Apparently, her appendix ruptured about a month ago. Somehow, her body formed some sort of internal abcess or something, containing all the bad stuff that causes serious problems. It was just begining to ‘leak’ when they operated, so it’s a good thing they caught it when they did. She has a minor something-infection, in her intestines, I think. So for now, she’s on a feeding tube (it’s apparently important to keep her stomach empty) and IV antibiotics to fight the infection. They also some some sort of irregularity in her heartbeat when she was under anesthesia, but that’s probably just because she had to miss a dose of her heart medication.
The main complaint that got her to the hospital was that she couldn’t work out in her garden: for an 84-year-old survivor of triple-bypass surgery, breast cancer, and 60 years of smoking, she’s amazingly spry. The doctor also said she must have an astounding pain tolerance, which I know for a fact is true. She’s an amazingly strong woman, there’s no doubt about that. On the other hand, she’s 84, has had some heart problems, just needed major surgery, and has a serious enough infection to require hospitilization.
So I’m trying not to worry - as my mom said, that’s not going to do anything. I wouldn’t overly object to some prayers/warm thoughts/psychic vibes/etc being sent her way.