Toronto Zoo's polar bear cub makes her happy sound in new video

Ever wanted to know what a polar bear cub sounds like when it's happy?

Well you're in luck.

The Toronto Zoo has posted new video of its six-week-old cub getting checked over. As the zookeeper scratches the cub's haunch, the bear can be heard "trilling," which the zoo describes as "the sound of a very content bear."

The cub whose sibling sadlydied shortly after being born is still considered to be in a critical stage in her development.

She's doing well, according to the zoo, who saysthe cub now weighs 2.1 kilograms and can fully open her eyes. Her nose and footpads have also turned black and she is teething.

The growing cub is also up to eating seven times a day, zookeepers say.