Thompson was born in Los Angeles to Julie and Mychal Thompson. His mother was a volleyball player in college for the University of Portland and University of San Francisco, while his father was the first overall pick of the 1978 NBA draft.[10] When Thompson was two, he and his family moved to Lake Oswego, Oregon, where he was childhood friends and Little League teammates with fellow future NBA star Kevin Love.[11] He and his brothers were raised there as Catholics.[12]