Ashlee Simpson's wedding to "Hunger Games" actor Evan Ross kicked off with a bachelorette party as sister Jessica Simpson stole the show with a plunging swimsuit that showed off her ample assets.

The bachelorette party for Ashlee Simpson's wedding to Evan Ross was hosted by Jessica Simpson at her Los Angeles mansion. She described it as a "Bohemian poll party," with around 20 of their close friends in attendance.

"Someone was on hand to help all the guests make flower wreaths," an insider dished out to People.

Her bachelorette cake was adorned with a throwback photo of the "Pieces of Me" singer. One of Ashlee Simpson's friends posted the cake on social media with the caption: "OH and thank you @mindyweiss for making my dreams come true with this cake!!"

Sister Jessica Simpson's plunging swimsuit was a show stealer. The fashion mogul even posted an Instagram photo of herself standing next to her friend along with the caption. "Oh yea girl ... we are proud to be in our bathing suits @baylormcg #hardworkpaysoff #workoutpartnerforlife."

She didn't forget who the bachelorette party is for, however, as she also posted a photo on social media of her younger sister wearing a crown of white flowers. She captioned the photo: "In love with this ethereal photo by @clsymonds of the beautiful, talented, co-designer of #JessicaSimpsonGirls and #bridetobe @ashleesimpsonofficial!!!"

Ahead of the Ashlee Simpson's wedding to "Hunger Games" actor Evan Ross, the tabloids have been reporting of her baby bump. But the rumors are proven to be false at this point. The 29-year-old has been hitting the gym to slim down in preparation for the big day.

"Hunger Games" actor Evan Ross had said in an earlier interview that he plans to be with her for the long haul.

"Honestly, we could go and get married right now, wherever," he said. "This is the most incredible time I could ever think of in my life and I'm young, but the same time, I've lived a different life than most and I can't think of a happier moment."