Justin Bieber’s heart  goes out for avalanna who died from brain cancer early Wednesday.

Avalanna Routh, aka “Mrs. Bieber,” was adored nationwide for her brave struggle with a rare and incurable cancer called AT/RT — and her unending love for the teen pop star.

“Our darling Avalanna went to Heaven this morning,” her family wrote on Twitter. “Oh Avalanna, the brightest star — you took our hearts with you, our greatest love.”

Avalanna, from Merrimac, Mass., hit headlines in February when she got the gift of a lifetime — a date with her beloved idol.

INSIDE AVALANNA'S DATE WITH JUSTIN BIEBER

Bieber learned about the young girl after her family started a “Get Avalanna to Meet Justin Bieber” campaign on Facebook and Twitter, using the hashtag, #MrsBieber. Avalanna was so infatuated with the singer her nurses once organized a pretend wedding, where Avalanna “married” a cardboard cutout of Bieber.

Bieber flew his cancer-stricken fan and her mother to New York for an early Valentine’s Day date, where they played board games and snacked on cupcakes and candy.

"Just got the worst news ever," Bieber tweeted after her death. "One of the greatest spirits I have ever known is gone. Please pray for her family and for her."

The singer called Avalanna "my angel," and added, "RIP Avalanna. I love you."

Dr. Charles Robert of the Dana-Farber Cancer Institute told The Associated Press Avalanna was diagnosed with cancer when she was 18 months old.

@justinbieber/via TwitterThe young girl died early Wednesday, her family wrote on Twitter.Justin Bieber/InstagramJustin Bieber posted this photo of Avalanna Routh on Twitter. 'My angel,' he wrote.

“[She] responded to initial treatment for quite a while, but the cancer kept coming back and ultimately she was no longer responsive.”

AT/RT affects the brain and spinal cord and usually occurs in young children. There are only about 30 new cases a year, Robert said.

The cancer institute called Avalanna a “very courageous young person who lived her life with grace and determination.”

WATCH the touching video of Justin and Avalanna here.

rmurray@nydailynews.com

Read more: http://www.nydailynews.com/life-style/health/young-justin-bieber-fan-avalanna-routh-dies-brain-cancer-article-1.1168887#ixzz27wZpNKPz

she was a young six year old girl who was fighting brain cancer she was a brave little girl . and she said all i want to do is meet justin bieber he was her idol so he parents an doctors began calling evey raido station they know till one day that dream came true justin flew her and her family out to meet him when she saw him her smile grew bigger and her face turn red he began seeing her alot more and she stated we are married now so every body knew her for mrs "bieber"  she was so happy justin was in her life thats all she would every talk about then on sep,26.2012 she died that hurt justin alot so im a supporter who is makeing this for that brave young girl