Hi
Welcome to the forum!
At your mother’s age the things you should look at are calcium deficiency and Vit D deficiency along with osteoarthritis, rheumatoid arthritis and probably gout too. The chronic pain in joints can be due to osteoporosis too.
Menopause itself can cause joint aches and pains and responds well to hormone replacement therapy.
It is normal for most people to feel the pain at night as this time all work is over and the aches and pains become more prominent.
I would strongly recommend you to consult a gynecologist and an orthopedic specialist and get these possibilities ruled out. It is difficult to comment beyond this at this stage. Please let me know if there is any thing else and do keep me posted. Take care!
Has she checked with the doctor to see if she has tendonitis or bursitis (re: shoulder)? Have they done a bone-density scan of her hips? Have they x-rayed her hips and shoulder to check for arthritis? Probably it's worse at night when she lays on the sore body parts and the pressure causes more pain? Does she use an eggcrate mattress?