Lester Gillis was burn in Chicago on December 6, 1908. During his early teens he worked on the streets with a gang of friends, doing minor crimes. By the age of 14 he was a car thief and had gotten his nickname baby face by the members of his gang. Nelson's early career included working for a chop shop stealing parts, running stills, and bootlegging. He also did multiple armed robberies.
In 1922 he was convicted of auto theft and sent to juvy. 2 months later he was released on parole, but within months he was sent back on the same charge.
He met a sales girl named Helen Wawzynak who he married shortly after.
Nelson was sentenced to a prison term of 20 to life in January 1931 for his armed robbery of a
bank in Chicago. After one year in the Illinois penitentiary he was being transferred to another prison and escaped. He ran to Sausalito California were he met his future gang member John Chase.
John Chase was born December 26 1901 and lived most of his life in California. He was a bootlegger for the mob connections in California. Nelson worked with Chase smuggling alcohol for a while. In 1933 Nelson was doing bank robberies in the Minneapolis and St. Paul area. He killed a resident of Minneapolis after a minor car accident and was wanted by the police in the region. Later in 1933 Nelson and Chase moved to Reno Nevada where Nelson worked as a hit man for the mob.
In 1934 Nelson, his wife, and Chase moved to Chicago and joined the Dillinger Gang, led by John Dillinger, then public enemy number 1.