Blake McIver Ewing (born March 27, 1985) is an American actor. He was known for playing Derek, Michelle's friend on Full House. Ewing also portrayed the role of Waldo in the 1994 feature film version of The Little Rascals. He was also the voice of Eugene on Hey Arnold!. Blake co-wrote and performed the song "Along the River", the end credit song to the film End of the Spear.