Does my mother qualify for any VA caregiver/aid support? She and my dad were married for 28 years before their 1979 divorce.

No, being divorced she gets nothing. Even if not, there are things she cannot receive. You can call ur local VA office to see if I am correct. SS wise she would be entitled to something if not already getting it.

It is called Aid and Attendence. Your local veterans group can help you with the application process. You need those papers but they should be able to help you retrieve them.

You need your dad's discharge papers to figure this out

Do you have any pictures of him in uniform?