Barrymore was born into an acting family. All of her paternal great-grandparents—Maurice and Georgie Drew Barrymore, Maurice and Mae Costello ( Altschuk)—as well as her paternal grandparents, John Barrymore and Dolores Costello, were actors, with John being arguably the most acclaimed actor of his generation. Barrymore is a niece of Diana Barrymore, a grandniece of Lionel Barrymore, Ethel Barrymore, and Helene Costello, and a great-great-granddaughter of Irish-born John and English-born Louisa Lane Drew, all of whom were also actors. She is a great-grandniece of Broadway idol John Drew Jr. and silent film actor, writer, and director Sidney Drew.