Were fruit brute and yummy mummy really classic cereals? I NEVER heard of those before this year. They both seem pretty close to frankenberry.
Negatory on fruit brute and yummy mummy. Only Frankenberry, Booberry and Count Chocula are vintage.
All five are actually vintage. Maybe your memory is failing you old-timer.

"In October 1971, the first two cereals in the line were introduced,
Count Chocula (originally called "Dr. Count Chocula") and the strawberry-flavored
Franken Berry. In February 1972, Franken Berry cereal included dye that turned some children's feces pink due to an inability to break down the heavily dyed breakfast food, a symptom sometimes referred to as "Frankenberry Stool."
Boo Berry, reputedly the first blueberry-flavored cereal, was released in 1973, and
Fruit Brute the following year. Fruit Brute was discontinued by 1984 and replaced in 1987 by
Fruity Yummy Mummy, which also had a short life as it was discontinued in 1993."