Kate Middleton will play a prominent role in the queen's Diamond Jubilee celebrations in 2012.

The brunette beauty - who will marry Prince William on April 29 next year - is reportedly being lined up to take a more public role when she joins the royal family and the queen has asked her future mother-in-law Camilla, Duchess of Cornwall, to help Kate adjust to her new duties.

A source told the Mail On Sunday: "After her marriage in April, Kate will really start to sort out her future role. The queen and Camilla will take an active interest and offer advice.

"The plan is for Kate to help pep up the Jubilee's youthful and glamorous face, while also underlining the continuity of the monarchy."

Although 28-year-old Kate's inclusion in the celebrations to mark the monarch's 60-year reign was Queen Elizabeth's idea, it is believed both William and Kate are delighted to have the opportunity to prove her credentials.

Kate has been criticised in the past for her lack of direction after she quit a job at fashion chain Jigsaw to work for her parents' party planning company.

The source added: "Kate is keen to dispel the image of her being workshy and William believes that

he can make the public see her as he does: as a caring woman of substance."