Corey Feldman first became well-known in the 1980s, as part of The Two Coreys, two teenagers named Cory/Corey who were popular on the teen fan circuit during that time.
And it is because of the popularity during this era, that many people wondered if he had appeared on a Little House on the Prairie, as there were many young cast members on the show, who would later become famous.
However, Corey did not appear on any episode of Little House on the Prairie during its run.