Police broke into a daycare centre in southeast Edmonton Wednesday night after staff locked up, forgetting about a three-year-old girl who was still inside.

The girl's grandmother was late picking her up, arriving at Rainbow Day Cares in the Mill Woods neighbourhood after 6 p.m. Staff had already closed the centre and gone home for the day.

'I think a step was missed in checking one more time before they left to make sure the girl was signed out.' — Nancy Ranu, daycare owner

The girl's parents phoned police, who broke into the centre and found the little girl still sleeping in a back room.

Nancy Ranu, the daycare's owner, said she will go over policies again with all staff as well as try to figure out what happened.

She said a co-owner made his rounds just before closing and reminded the two remaining staff members, who have more than 20 years experience, not to forget about the sleeping girl.

"And because he had already made his rounds, it's just, I think, a step was missed in checking one more time before they left to make sure the girl was signed out," Ranu told CBC News.

She said she also expects to meet with Alberta Children's Services and city officials.

Clients dropped off letters of support for the daycare Thursday morning.

Bill Lylick, whoseseven-year-old grandson attends the centre,thinks the facility has all the necessary checks and balances in place.

"Things happen. The thing with this is thatwhen I come here and I pick up the grandson, they make sure that the right person is picking up the right person at the right time," he said.

"Their field trip activities have been fantastic.I just feel I have to support them."