Grammer was born in Los Angeles, California to actor Kelsey Grammer and make-up artist Barrie Buckner. Her parents were never married. Through her father, she has three half-sisters: Spencer (born 1983), Mason (born 2001), and Faith (born 2012) and three half-brothers: Jude (born 2004), Gabriel (born 2014), and James (born 2016). She was raised primarily by her mother in Malibu, California. She was named after actress Greer Garson.