Cook lemon pie filling with eggs and water according to package directions. Cover surface of pie filling with plastic wrap to prevent a film from forming; refrigerate until cold.
Blend 2 cups (500 mL) of whipped topping into the lemon pie filling; spoon into dessert dishes and chill.
Mash raspberries with fork. Blend into remaining whipped topping. Before serving, spoon raspberry cream on top of lemon mousse.