Justin Bieber is mourning the loss of his biggest and cutest fan today.
Avalanna Routh, referred to by many who knew her as "Mrs. Bieber," succumbed this afternoon to a long battle with cancer. She was six years old.
In February, due to a persistent Facebook campaign, a visit was arranged between Routh and Bieber in New York City.
The two spent hours there playing Candyland and exchanging playful kisses and hugs.
"just got the worst news ever," Bieber Tweeted after learning of Avalanna passing. "one of the greatest spirits i have ever known is gone. please pray for her family and for her. … RIP Avalanna. i love you"
Jessica Biel also honored Routh this month at the Stand Up to Cancer fundraiser, relaying her story to viewers and later telling the patient on Twitter:
"you're my hero."
Our thoughts go out to Avalanna Routh's family.