Eileen, 59, enjoyed a wild weekend with her husband Vincent Van Patten and some of their friends.
She wore her season 6 RHOBH reunion dress during one of the outings.
One of Eileen's stops in Sin City was seeing pop icon Janet Jackson perform at the MGM Las Vegas.
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Beyonce and Kelly Rowland were also spotted at the "Escapade" singer's show over the weekend.
"JANET!!!!" Eileen captioned an Instagram snap of her with Vincent and their pals. "Vegas whoop!!!!!!!"
Eileen also posed with her brother-in-law Jimmy Van Patten at a Janet after party.
What are your thoughts on Eileen's fun Vegas weekend? Sound off in the comments!