A Brampton teenager claiming to be Ellen DeGeneres' biggest fan proved her loyalty in a trivia contest and won $15,000.

Leah Borneman, 18, responded to a call on DeGeneres' website asking for Canadian fans to write in to the show. She wrote to the TV host, telling DeGeneres that she first started watching the show with her grandmother.

"She was diagnosed (with Alzheimer's) when I was 10 years old," Borneman told CTV's Canada AM on Wednesday.

Though Borneman said her grandmother eventually didn't recognize her in her final days, they'd watch DeGeneres' show and laugh together.

Borneman was working at a No Frills in Brampton on Tuesday when she got a phone call from someone claiming to be a customer. The "customer" was DeGeneres.

Borneman was asked a series of trivia questions as part of the show's "Cash at Your Store" segment, and won $15,000 to go towards post-secondary education.

"I've seen (DeGeneres) do all this for so many other people and now to think I'm one of them is just beyond belief," Borneman said.