Lexi Hood was playing peek-a-boo with her father, Gareth, and mother, Charlene, 31, at home in Bridgend, Wales, when she was suddenly knocked to the ground.
Mr Hood, 35, said his daughter, who he described as 'sturdy on her feet', said 'naughty boy' as if she was telling someone off.
He added that strange creaking sounds had been heard in the house ever since.
The clip, taken while the family was watching a film three weeks ago, shows Lexi standing in front of the TV with her hands over her eyes.
Giggling, she peeks at her father before suddenly falling to the floor - her arms out to the side as if being pushed or pulled.
But the toddler appears unfazed by the mysterious bump and continues to gurgle happily on the floor.
Watch the video below..