Seriously, JLo, what's your youthful secret?

Before her big 45th birthday bash yesterday, Jennifer Lopez took to Instagram to post an intimate bathtub selfie.

The 'American Idol' judge looked beautiful and relaxed as she soaked in a tub of bubbles and flower pedals on the night of her party. "Soaking it all in... #birthdaygirl #itsmyparty #quietbeforethestorm" she wrote in the caption of the picture.

According to Huffington Post, Lopez was in Southampton, New York for her big night, which included a star-studded list of celebrity guests. Some of the notable attendees included Kelly Ripa, Leah Remini, French Montana, Khloe Kardashian and JLo's rumored boyfriend, 'Dancing With the Stars' pro Maksim Chmerkovskiy.

Lopez later posted a photo of her looking glamorous at her party with the caption "Let the games begin! #itsmyparty #funtimes #birthdaygirl #aintnuthingbutanumber"

Auditions for Season 14 of 'American Idol' began last month in Minneapolis, Minn. and will continue through the summer. Lopez will return to the judges panel with Harry Connick Jr. and Keith Urban. 'American Idol' Season 14 premieres in January 2015.

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