The problems would usually start when the joey came back and tried to enter the pouch. Some mothers would shoo the joey away as they’d feel the dosseroo in the pouch and assume it was their baby. Other mother kangaroos would recognise the joey and try elaborate methods to extricate the dosseroo, even occasionally insisting that a male kangaroo kick their pouch very gently to make the dosseroo leave.
After the 24-hour period was over, the dosseroo would usually leave the pouch to eat some vegetation before lying down on the ground to wait for another joey to leave a mother’s pouch.
Excerpt from – Animals Evolution Avoided