Get an MRI scan, visit a Dementia Care Center or go to medical school.

I wouldn't bet on it. The HIPAA rule deals with the privacy of
medical records, without that person's authorization, you're out of luck.

Cheers

How can I tell if someone is the early stages of Alzheimer’s or having
mini strokes?
Can I call their Doctor and make them aware of this person’s action
and ask them to for their opinion?

She needs a full evaluation which may consist of a PET scan to look for
specific shrinkages in certain areas of the brain, a psychological test to
see if her memory is impaired and how much, a blood test for thyroid
disease, testing for the amount of B-12 in her blood, and testing to rule
out things like NPH... normal pressure hydrocephalus.

Many things can cause forgetfulness, and some of them are entirely
reversible with proper treatment.   A diagnosis of alzheimers is made by
ruling out the other possible causes.

Do you have power of attorney?   Certain legal papers ought to be in place
at this time, because she may need someone to make decisions for her.

Good luck!

You can talk to their doctor, but because of HIPAA privacy rules,
the doctor may listen but not discuss the patient's condition.