<P> Jeremy Foley (born Geronimo Jeremiah Foley on February 20, 1983) is an American actor . Foley is perhaps best known for his appearance as Billy in the Buffy the Vampire Slayer episode "Nightmares", as well as his supporting role of Griffen Lowe in the Nickelodeon show Caitlin's Way . </P> <P> Foley also played Graham in the 1997 film Dante's Peak and voiced the titular ghost in Casper: A Spirited Beginning and Casper Meets Wendy . He also played Clay in the 1999 movie Soccer Dog . </P>

Who plays billy in buffy the vampire slayer