Pictures of Connor, 7, and Noah Barth, 5, cleaning a 14-foot African rock python's cage were posted by their mother Mandy Trecartin on her Facebook page.
The Barth brothers were strangled in their sleep by the same python, "Mr. Slithers," on Monday morning.
The brothers were sleeping in an apartment that is part of the same building as the "Reptile Ocean" pet shop and museum, located in Capbellton, New Brunswick, Canada, noted the Daily Mail.
Reptile Ocean is owned by Jean-Claude Savoie, who kept the python in a second-floor apartment above the pet store.
Savoie told the Global News that he found the boys at 6:30 a.m. on Monday.
"They were sleeping, but they didn't even open their eyes or nothing. I thought they were sleeping until I [saw] the hole in the ceiling. I turned the lights on and I [saw] this horrific scene," said Savoie.
"[The snake] went through a ventilation system. I don't understand how it did it. It went through the ceiling... and the snake fell into the living room from the ceiling."
Savoie found the snake coiled in a hole nearby, held it down and put it in a cage.
He said the boys were the sons of his best friend, Trecartin, and they often slept in the living room.
Royal Canadian Mounted Police ordered the python destroyed on Tuesday. The python's carcass was taken to a local zoo to be examined.
Savoie could face criminal charges.
"It is illegal for anyone to keep any exotic species that is not listed in the regulation unless they have a permit from the Department of Natural Resources," said New Brunswick government official, Steven Benteau.
"If such an animal is found, it will be confiscated and the person who possesses the animal can be charged under the Fish and Wildlife Act."