Publicists told People magazine the celebrity couple tied the knot at Simpson's parents' home in front of 150 close friends and family Saturday night.
"We're delighted to confirm that Pete Wentz and Ashlee Simpson were married this evening in front of family and close friends," the representative said.
Pop star Jessica Simpson served as the maid of honor for her younger sister and the singers' father, Joe, performed the non-denominational ceremony.
Simpson and Wentz had planned their wedding ceremony based on an "Alice in Wonderland" theme.
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