Two fathers and two sons went fishing one day. They were there the whole day and only caught 3 fish. One father said that is enough for all of us we will have one each. How can this be possible?

3 generations. A grandfather, a dad, and his son.
Grandfather and dad = Two fathers
Dad and his son = Two sons

Both fathers had their credit cards to buy more food?

One of them is vegan.

it was a grandfather, a father, and a son

@ENDQUOTE this is wonderful. Very interesting.

Grandfather, son, grandson

There is a grandpa, a dad, and a grandson. The dad and the grandpa are both dads and the dad and the grandson are both sons.

Father, son, grandfather.