Mammas - Season 1 Episode 3 Cuckoo

Good babysitters are hard to find, so Mamma Cuckoos use some slight-of-wing to trick other birds into hatching and raising their young. They slip their eggs into the nests of smaller birds. When the Cuckoo chicks are born they knock those other eggs out of the way and convince their fake Mammas to feed them instead. It sure cuts down on childcare costs!