Park the car

a boy walks in on his mum in the shower, he looks at her croch and asks whats that and she replies thats my garage.later the boy walks in on his dad in the shower, he looks at his dads croch and asks what that to which his dad replies thats my car. the next day the boy walks in on his mum and dad in she shower together having sex and the boy asks”daddy, whats your car doing in mummys garage”?