Atwood faked 'accidentally' launching his son within the bannister, while they certainly were playfighting on the landing.
Understandably, his wife didn't begin to see the funny side. All of it starts innocently enough. When Atwood's wife returns home she sees her husband innocently playfighting using their sons on the landing.
Atwood asked his wife to fetch him one cup of water from the kitchen.
While she's is in the kitchen, Atwood swaps his son for a mannequin wearing the exact same Spiderman suit as his youngest.
As his wife climbs the stairs, Atwood pretends to carry on having fun with the doll and 'accidentally' kicks it within the banister to the room below. Watch the video below.