Avi was born in New York City in 1937 but was raised in Brooklyn. His twin sister gave him his name when they were about a year old. He doesn't give out his real name because "Avi" is the only name he uses. As a child, he struggled with school. In elementary school, he had trouble writing. In high school, he failed all his courses. At that point, his parents put him in a smaller school that focused on reading and writing. Even then, he still needed special tutoring. Despite the struggle, he stuck with writing because he wanted to prove to everyone around him that he could write. It wasn't until he had children that he began to write for young people. He has written all types of books including animal tales, historical fiction, mystery, adventure, and fantasy books. His favorite book out of all he has written is Ereth's Birthday. For those people who want to write, he says that "reading is the key to writing. The more you read, the better your writing can be."