(Photo Credit: Jordan Strauss/Invision/AP)

It was an extended family affair at "The Hunger Games: Mockingjay - Part 1? premiere Monday night.

Jessica Simpson, accompanied by husband Eric Johnson, showed up wearing a vintage gold one-shoulder gown with a thigh-high slit that displayed her seriously toned leg.

While she may have stolen the show on the Los Angeles red carpet, Simpson was there in support of sister Ashlee's husband, Evan Ross, who has a role in the movie opening Friday.

Ross was not only accompanied by his new wife but his famous mom, Diana Ross, who flew in from her concert tour to attend her son's premiere event.

(Photo Credit: Jordan Strauss/Invision/AP)

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Later, the family got a little rowdy inside L.A.'s Nokia Theater when Ross, who plays Messalla, Cressida's assistant from the Capitol, first appeared on screen.

"When my face showed up onscreen the first time, everyone jumped up. The whole group. It was unbelievable," Ross told USA Today.

After the film, Ross and the two Simpson sisters, along with Jessica's husband, kept the party going at the film's lavish after-party.