The Disney+ original movie, Noelle, is one of my favourites. To be fair, my kids enjoyed it too, pretty much the whole time, but the entire plot of Noelle trying to find her missing brother Nick, who is supposed to be Santa Claus, was lost on them. They did like all the scenes at the North Pole and the ones featuring Santa, so it was enough to pique their interest (although I wouldn't rely on it if I was looking for a solid hour-and-a-half movie time).
Watch Noelle on Disney+.