Elsa can't bring her snow creations to life when she tries to. She has to do it in the moment, brimming over with confidence and creativity.

When Anna's around more are produced than not and eventually there are more than the castle staff. They know nothing but the love of snow and Elsa would dismiss them but they're alive and Olof loves each and every one of them.

Elsa lets him name them after the 7th. He teaches them, trains them, and eventually there are so many snow clouds floating around the castle that heating the place is next to impossible (on top of the fact that this is the Ice Queen's domain).

Everything from mice to dragons and Anna has a horse, she's getting used to the cold. Elsa has a living book shelf that never drips on her books and their favorite maid has a mop that loves to clean.