BOSTON (AP) -- The 6-year-old Massachusetts girl whose love for Justin Bieber encouraged hospital workers to organize a pretend wedding to the pop singer as she battled a rare form of brain cancer has died.

The family of Avalanna Routh said on their Twitter account that she died Wednesday.

Her pretend wedding to Bieber led to a social media campaign to help her meet Bieber.

Bieber later arranged for the child and her parents to meet him in New York, before he tweeted that the experience was the most inspiring in his life.

Routh was suffering from an atypical teratoid rhabdoid tumor. Only 30 new cases are diagnosed in the U.S. each year.

The Dana Farber Cancer Institute mourned Routh's passing, saying she raised awareness about the disease and the need for greater research.