Allison Tate wrote a wonderful piece in her blog encouraging mothers to get into their family photographs. http://allisonslatertate.com/
My sisters and I are going through photographs with our mother, and are grateful that both she and my father enjoyed taking pictures, with dad mainly taking colored slides, and mom taking black and white photographs. So, they both show up relatively frequently.
I have tried over the years to have an annual photograph of our family for Christmas cards. I have them together in one book, documenting us aging over 25 years.
I always enjoy getting photographs that include my friends, and not just their children.
When I visited Andy's mother this summer she gave me photographs of Andy as a child and of her parents.
I do wish we had pictures of Andy's father with his family. There are none. Andy's parents divorced and what photographs there were are no more.
I do not blame my mother-in-law. They may have been painful to look at. She may have given them to Andy's father. They may have been lost in a move.
What I do encourage is for aunts and uncles to step in when there is a divorce and offer to store these photographs that may be too difficult in the immediate, but may be valued years later. I saved Andy's sister's wedding snapshots (the ones we took) after her divorce should her daughter want them someday. I offered to take in the formal portraits, wedding dress and wedding rings, but that was declined.
So, moms, get in the picture. And aunties of a divorcing family, set aside a drawer for memories that may be wanted later.