Kristen Bell calls terminally ill fan

London: "House of Lies" actress Kristen Bell made a special call as Princess Anna from "Frozen" to a 6-year-old girl suffering from brain tumour.

The 35-year-old actress called Disney fan Avery, who was diagnosed with an inoperable brain tumour last month, reported Daily Star.

Writing on her CaringBridge page, her father, Brandon Huffman said, "Although the last 3.5 weeks (have been) a nightmare for our family. There are occasionally days when they're just able to forget... The awful battle she's going through.

The clip of the girl giggling after talking to her favourite character Anna has gone viral.

"I've watched the video of her hearing from Anna/Kristen Bell, around 50 times, just to watch her face light up, and to hear her giggle and see her smile," her father said.

"Seeing it go viral and so many people sharing the same emotions I have when I watch it, I'm constantly reminded that while Avery is going through the worst possible fight anyone should have to, she is touching so many people's hearts and her fight and toughness is reaching so many people," he added.