Selena Gomez took a back seat to Avalanna Routh, 6, for Valentine's Day time with Justin Bieber this year and we're betting she did so with a smile. Avalanna, a little girl from the Boston area known as "Mrs. Bieber," is suffering from a rare and aggressive form of cancer called ATRT that she has battled for most of her life, but not even that dampens her love for The Biebs.

After an online campaign featuring Avalanna espousing her love for The Biebs landed in front of the singer's eyes, he flew her and her family to New York City on Monday (Feb. 13) so they could have a "date." OMG, precious is not the word for it.

The Biebs and the "Mrs." played board games, ate cupcakes and signed autographs for one another. But perhaps the highlight of Avalanna's day was the fact that she got to style The Biebs' famous coif. Avalanna earned the "Mrs. Bieber" moniker last year through a pretend marriage via the Jimmy Fund.

The Biebs tweeted a photo of his time with this angelic little girl, writing "Best part of my day." He also tweeted: "got some really great ideas from today. ways to #giveback - #MrsBieber really inspired me. Really."

During her date, Avalanna copped to loving the Biebs for "seven years. No, 80. Eighty years." That's about 74 years longer than she's been alive and about 62 years longer than The Biebs himself has been alive. So adorable, right? She also admitted to having Bieber fever.

What a sweet guy The Biebs is to have made this little girl's day with a date! We applaud him for using his fame for good and for being so kind to sick kids. As for Avalanna? Well, the whole digital world is pretty much crushing on her. How can they not be?  But alas, she belongs to The Biebs.

Watch Justin Bieber's Valentine's Date With Mrs. Bieber