X Factor wedding singer Katie Waissel

Katie as the maid of honour at Natalie's wedding

Katie as the maid of honour at Natalie's wedding

Katie Waissel has had more experience singing in front of an audience than she has let on.

The X Factor star delighted guests at her older sister Natalie's wedding in 2006 to Glenn Davis, with a rendition of Fred Astaire’s “The way you look tonight”.

“It was her way of showing how much she cared as a sister,” said Mrs Davis, who at 27 is three years older than Katie.

The wedding was held at the New West End Synagogue in London, the community Katie’s grandmother still belongs to. Mrs Davis said her sister made sure that the day was special.

“She was my maid of honour and she helped organise the hen night. She also did the toast to the Queen.

“She was brilliant at the Israeli dancing too,” said Mrs Davis. “Everyone in our family knows how to let our hair down.”

Mrs Davis, who has two young sons, said Katie’s showbusiness ambitions don’t get in the way of her being an aunt.

“She’s still very much a family girl, on festivals and Friday nights. She still has a normal side. "

She added: “The boys love her and love to watch the show. Harrison, who is three, went up to a woman in Westfield this weekend, tapped her on the shoulder and said ‘my auntie Katie has the X Factor’.”

The sisters used to work together at the family’s Pinner clothes shop, DNK. Mrs Davis said Katie has always been fashion orientated and had “a quirky dress sense”.

“She’s always known how to dress up an outfit. Now people are coming into the boutique wanting the Katie look – she’s making that much of an impact.”

Katie has been in the bottom two of the X Factor five times already, but been saved, provoking an outraged reaction from some fans. Her sister said the negative publicity has been difficult for the family.

“Simon has said any publicity is good – we have to take it as a compliment that she is in the centre of the X Factor.”

“She deserves to win,” said Mrs Davis. “She’s had a hurdle every week and got over it every week. She deserves praise for it.”

“I’ll support her, whatever happens, though,” she said. “We used to argue a bit but as we’ve got older the age gap has closed up and now we’re closer than ever.”

Katie Waissel's family album

Last updated: 12:11pm, November 18 2010