Carl was born and raised in the Johnson family home in Ganton, Los Santos. His mother was Beverly Johnson, and he had three siblings, Sean "Sweet" Johnson, Kendl Johnson and Brian Johnson. Carl says he never knew his father, despite Old Reece mentioning his father countless times.
He also grew up with Big Smoke and Ryder, two people who lived on Grove Street with the Johnson family. In 1984, Carl's brother, Sweet, became the leader of the Grove Street Families gang, with Carl also joining it. The gang experienced its peak in 1985, but later went into decline between 1987 and 1992, after being pressured by C.R.A.S.H. and Frank Tenpenny, one of the officers in that unit.
It was around this time in 1987 that Carl's other brother, Brian, ended up getting killed, which Carl blames himself for, as well as Sweet. This causes Carl to leave San Andreas and move to Liberty City, where he ended up working for Joey Leone, doing small-time crimes. However, in 1992, Carl received a call from Sweet saying that his mother was killed in a drive-by, causing him to return to Los Santos.