klein was born and raised in irvine, california. klein is a middle child, in a jewish family. his father, abel klein, is a mathematics professor at university of california, irvine. abel klein is from brazil. his mother is an artist. klein went to school at university high school. he went to the university of california, santa cruz, but transferred to the university of california, los angeles. he graduated from ucla in 2005 with a b.a. in political science.