A young girl who inspired hundreds of thousands through a series of makeup tutorials posted regularly on YouTube has sadly passed away, her family confirmed this afternoon.

13-year-old Talia Joy Castellano was diagnosed with neuroblastoma in 2007, and had since fought valiantly against the disease through a two aggressive resurgences.

While undergoing treatment, Talia found strength in recording makeup tutorials, which she posted on YouTube to the delight of nearly 800,000 subscribers.

She would also take the time to raise awareness for her condition and the conditions of other cancers patients both young and old.

Boing Boing's Xeni Jardin ran down the list of the amazing amount of things Talia's managed to accomplish in her tragically short life:

Cover Girl made her an honorary "covergirl;" she appeared in a People Magazine ad; was interviewed on The Ellen Show. She produced a namesake clothing line. She was featured in a documentary advocating for more childhood cancer research. She was also a spokes-kid for Base Camp Children's Cancer Foundation, which has launched a new project in her memory.

Ellen mourned Talia's passing on Twitter, telling her followers, "This year I met a very special girl, and today we lost her. Sending my heart to Talia's family. I'm so sad."

[photos via Facebook]