ok, I will try.

your chain A->B->C->D

Granting is the opposite. D->C->B->A

Each toon can grant a maximum of 30 levels to another toon.

D is at 60, can grant 30 levels to C's toon until they get to 60.

So most people play 2-3 groups to 60. Then level some toons to 30. (1-30 is faster then 30-60)

Grant levels. you will have a lot of levels to chain grant to make more 60s.