Ashlee Simpson was almost four hours late for a launch party, because she was getting "dolled" up by sister Jessica.

The 22-year-old singer asked her elder sibling to work her magic on her before the Armani Exchange Sunglasses bash last week.

However, Ashlee's make-over took longer than anticipated and she arrived three-and-a-half hours late for the party, which was hosted by pal Nicole Richie.

When asked why she was so delayed, Ashlee's boyfriend, Fall Out Boy rocker Pete Wentz, joked to the New York Daily News newspaper: "She spent over an hour getting dolled up for the night by her big sis'."

The young star - who refuses to deny or confirm reports she had a nose job in April 2006 - recently stated she believes plastic surgery should be a "personal choice".

She said: "I don't get bothered by people saying what they say. I'm a happy person and I'm happy with my looks. I'm not an insecure person.

"I believe if somebody chooses plastic surgery it should be for themselves, not for anyone else."

It was claimed last year that Ashlee turned to surgery because she felt like an "ugly ducking" next to singer-and-actress Jessica, 26.