I was the main person tickling in my family. But one time, and one time only, did I see my dad tickle my mother. He was a big rugged guy and mom was small. I was in the living room watching TV and all of a sudden I heard screeching laughter coming from the kitchen. I looked in there and saw my dad holding my mom's ankle with her on her back on the floor, He was tickling the hell out of her foot and she was going ballistic laughing! She was spinning around on the floor while he had his fun. It only lasted a short time but around 60 years later I can still remember what I got to watch!!!!