A teenage Blanket Jackson has dropped the nickname that unfortunately stuck with him throughout much of his childhood thanks to his famous father, Michael Jackson.

The King of Pop's youngest son "changed his name informally from Blanket to Bigi" before he entered the seventh grade at The Buckley School in Sherman Oaks, Calif., a source told Radar Online.

The 13-year-old Jackson suffered terrible bullying from his classmates due to his unique moniker. Bigi has a German origin and means idealistic, sensitive and inspirational.

Born Prince Michael Jackson II, his father called him Blanket as a nickname. "He always thought that the name Blanket sounded so stupid and resented his father for calling him that," the source said.

The name made him an easier target for his peers, who were already mean to him "because of their jealousy" of who he was.

Jackson's most recent yearbook photo identifies him as Bigi Jackson. He's still sporting his long hair, but an insider at the school described him as "a very good student" to Radar.

"He is really sweet, funny and helpful," the source told Radar. "He volunteers to help the younger kids and he is really good with them."

Jackson and his 17-year-old sister Paris are under the care of their grandmother, Katherine, and cousin, Tito Joe "TJ" Jackson. Older brother Prince just turned 18 years old and will attend Loyola Marymount University in Los Angeles this fall.