Lawrence was born in Abington Township, Pennsylvania, the son of Donna Lynn (née Shaw), a personnel manager, and Joseph Lawrence, Sr. , an insurance broker. His family's surname was changed to Lawrence from Mignogna before he was born. He is of half Italian, English and Scottish descent. He is the middle-born of three boys; with two brothers, Joey Lawrence and Andy, both of whom are also actors. Lawrence attended classes at Abington Friends School.