Ashlee Simpson reportedly wants her wedding preparations to be stress-free.

The 29-year-old star is gearing up to wed her fiancé Evan Ross later this summer, marking the second time she will have walked down the aisle.

Ashlee's older sister Jessica tied the knot with former American football star Eric Johnson earlier this month, with the wedding making the younger sibling think about what is important to her.

"She actually doesn’t have wedding jitters," an insider told

"Seeing how much went into planning Jessica's wedding, Ashlee wants to take the time to enjoy the wedding process and every minute before it comes."

Jessica and Eric exchanged vows at Montecito’s luxury San Ysidro Ranch, with 250 family and friends looking on as they did so.

It's thought that Ashlee and Evan's wedding will be held over the upcoming Labor Day weekend, which is at the very end of August. It's expected to take place at Evan's superstar mother Diana Ross' home in Connecticut, with Ashlee apparently relaxed about the details.

"She loves that her mother is assisting with planning the wedding," the insider said.

It's thought there is just one thing Ashlee is determined to have on her special day - she wants Diana to perform for her guests.

There's previously been speculation that the younger sister is planning a very different party to her sister. Jessica's wedding was a traditional affair, with 12 bridesmaids, 11 groomsmen and Jessica in a champagne and gold Carolina Herrera gown. In contrast, Ashlee is said to be going for more of a bohemian vibe.

She was previously married to Pete Wentz, with who she has five-year-old son Bronx. Jessica was previously married to Nick Lachey and she has two children with Eric.