Wow, Just Wow!

My oldest sister, my wife and I had to go clean out my recently deceased father’s house. Mom had passed over 10 years ago and Dad basically turned into a recluse, drinking and rarely leaving the house or interacting with the family. My younger sisters never forgave him, especially for never meeting his grandchildren.
While throwing out almost everything, my wife found an old locked steamer trunk in the back of the deep closet in my fathers bedroom. When we broke the lock and opened it, it was full of old porn magazines and vhs tapes. It wasn’t until we dug through them that we found out that Mom did hardcore porn before and during their marriage. Mom was very attractive , and did Facials, gangbangs, lesbian and even lactation! Mom did porn while pregnant! This obviously shocked us, but also there were letters that Dad had written to here after her passing, swearing he would always love her.
My sister wants to tell her sisters, but my wife and I think we should destroy the evidence and let the secret die.