Grandma had so many different Jell-O salads...but this is the first one I found in my recipe files.
Grandma Mary’s Jell-O Salad
3 small boxes jello, 4 cups boiling water. Mix until jell-o is dissolved. Add 1 can matching pie filling. Mix well. When jell-o starts to gel, add 1 tub of cool whip and mix together.
(Methinks I took this recipe verbatim from a phone call.)