Mattel issued a large line of plush of the Muppet characters based on The Wubbulous World of Dr. Seuss in 1997. Among the characters released were small versions of Horton the Elephant, Yertle the Turtle, and Thidwick the Moose. Each plush also came with various "Whosits" and other characters.
The highlight of the collection was a child sized Cat in the Hat plush.
A child sized Horton was featured in Mattel advertising, but it is unknown if he was ever produced.