This video says about itself:
27 January 2016
A Red-necked Grebe sits on its nest in Alaska, and a young chick climbs under its parent’s wing. These birds‘ nests are placed on aquatic vegetation, sometimes in open water, and are anchored to the lake bottom or submerged logs. Nests are a floating mound of plant matter with a depression in the middle, and the bulk of the nest is below the water line.
After hatching, chicks climb onto their parent’s back, where they spend most of their time until they are 10 to 17 days old. The chicks’ downy feathers are not waterproof like adult feathers, and young rely on their parents to keep them warm.