Animaker

A young reindeer named Niko dreams about flying like his father, whom he has never met. Despite constant teasing from others, he sneaks out of his home valley to take flying lessons from Julius, a flying squirrel.

Set right before Christmas, young reindeer Niko must deal with his mother's remarriage and his being tasked with looking after his little stepbrother.

Niko the reindeer joins his father in Santa's Flying Forces, but when Santa's sleigh is stolen by an acquaintance, Niko must find it in time for Christmas.