Credit: Lester Cohen/

Just days after giving a heartfelt performance that ended in tears at her Mohegan Sun concert in Montville, Conn. Saturday, Jennifer Lopez put on a brave face and stepped out for a charity press conference in West Los Angeles on Tuesday.

With her hair twisted into a high "fun bun" (Lauren Conrad's fave hairstyle), Lopez switched directions from her sexy, sequin-adorned bodysuits and wore a polished, sophisticated sky blue Lisa Ho cocktail gown with criss-cross detail on the chest, which she accessorized with Brumani and Isharya jewels.

She was accompanied by her younger sister, Lynda Lopez, to support the Maribel Foundation, a non-profit organization the star formed in 2009 to improve healthcare for women and children in need.

The "On the Floor" singer announced the foundation's partnership with Samsung and Best Buy, who have pledged to donate up to $500,000 to the cause from the sales of select Samsung products.