Kate Middleton and her younger sister Pippa attended their friend's wedding ceremony on Saturday in Wilton, Wiltshire in England, accompanied by Prince William and Pippa's boyfriend Alex Loudon.

Kate dazzled the nuptial by appearing in a red lace knee-length dress designed by Collette Dinnigan and wore a matching fascinator and sexy Prada platform pumps.

In order to prepare for her friend's nuptial, Kate spent 4 hours in her favorite hair salon on Friday afternoon. The service included coloring Kate's hair with organic vegetable-based hair dye, trims and treatments.

Kate usually spends time and socializes with people in the salon for eight years. And, even after she became a royal princess, she still continues to come to the salon once every two months.

An insider told US Magazine, “She loves her time there and she has known everyone there for years so it's really relaxing for her."

Her family, including her mother Carol Middleton and Kate's little sister Pippa Middleton, have been trusting the hair salon for several years.

Pippa, who looked happy with Alex at her side, chose a grey-and-white floral-printed frock and black fascinator for the ceremony. No wonder, the rumors about their impending wedding have gone viral on the Internet.

“They are very much an item and Pip tends to stay at his place on a Wednesday, Thursday and often Friday night,” a friend of the Middleton family said in a report.

Moreover, Alex also has impressed Pippa’s family and friends. “William, Kate and Pippa’s parents adore Alex. They trust him and see him as one of the family. They’d be very happy if he slipped a ring on Pippa’s finger,” a source revealed.

The designer Alice Temperley, who designed the wedding dress for Kate, is ready to design wedding dress for Pippa. “I’d love to dress Pippa for her wedding when it happens,” Temperley said. “She’s so beautiful – she’s perfect, and her bum is perfect – it would be such an honor.”

Temperley has dressed all the women in the Middleton family, including Kate, Pippa and their mother Carol Middleton. Both her ability to create stunning gowns and keep secrets have impressed the Middleton family.

The younger sister of the Duchess of Cambridge, socialite Pippa Middleton attended a wedding of a close friend in a striking dress from Dannii Minogue’s fashion line, Kate Middleton was also spotted in the ceremony and was as equally stunning as her younger sister. Choosing to stick with a classier style, the Duchess wore a red laced dress by designer Collette Dinnigan

Britain's Prince William and Catherine, Duchess of Cambridge arrive at the Summerfield Community Centre in the Winson Green area of Birmingham, central England August 19, 2011.

Sarah Burton gained global praise when the Duchess of Cambridge wore Burton’s Royal Wedding dress creation.

Kate wears a favorite green Diane von Furstenberg dress to a private reception at the British Consul-General's residence in Los Angeles July 8, 2011.

File photograph shows Britain's Prince William smilling as he walks with his girlfriend Kate Middleton at RAF Cranwell, central England

Prince William and Kate Middleton

Prince William and Kate Middleton have received around 60,000 cards and letters from the public wishing them a happy married life.

Britain's Prince William watches as his wife Kate Middleton, Duchess of Cambridge wields a shovel to plant a tree at Rideau Hall in Ottawa

Prince William and Kate Middleton

Prince William and Kate Middleton

Britain's Prince William and his wife Catherine, Duchess of Cambridge, pose for pictures at Yellowknife airport

Britain's Prince William and his wife Catherine, Duchess of Cambridge, wave as they board a Canadian air force jet at end of their royal tour of Canada in Calgary

Britain's Prince William and his wife Catherine, Duchess of Cambridge, sporting cowboy hats and costumes in Calgary.

The sister of Catherine, Duchess of Cambridge, Pippa Middleton and former English cricketer, Alex Loudon, sit on Centre Court at the Wimbledon tennis championships in London June 29, 2011.

The parents of Catherine, Duchess of Cambridge, Michael (L) and Carole Middleton (2nd L), her sister Pippa (3rd L) and former English cricketer, Alex Loudon, sit on Centre Court for the quarter-final match between Jo-Wilfried Tsonga of France and Roger Federer of Switzerland at the Wimbledon tennis championships in London June 29, 2011.

Pippa Middleton, sister of Catherine, Duchess of Cambridge, watches the match between Maria Sharapova of Russia and Agnieszka Radwanska of Poland during the French Open tennis tournament at the Roland Garros stadium in Paris, on May 30, 2011.

Pippa Middleton leaves The Goring Hotel in central London, on April 30, 2011.

Pippa Middleton, sister of Catherine, Britain's Duchess of Cambridge, watches the match between Maria Sharapova of Russia and Agnieszka Radwanska of Poland during the French Open tennis tournament at the Roland Garros stadium in Paris May 30, 2011.