The San Mateo County Coroner's Office has identified the girl as Naretzi Navarrete of Merced.
Navarrete and a 54-year-old man were swept by a wave at the beach on Saturday.
Authorities rescued her and took her Stanford that evening.
The Coast Guard announced Sunday she was pronounced dead.
Before the announcement of her death, the Coast Guard suspended the search for the man who is still missing.
The Coast Guard said crews searched for approximately 22 hours and scoured 100 square miles.
The agency confirms the victims are related as grandfather and granddaughter.
There was a Beach Hazard warning for the coastline this past weekend of potentially deadly sneaker waves.