Ms Lopez who shares care of five-year-old twins Max and Emme with her ex-husband Marc Anthony - says she was very worried about the little boy, who she has nicknamed 'The Boss', when he fell recently requiring stitches but was reassured when he started laughing about his injury.
The 43-year-old singer and actress told People: "I hear that all little boys have a scar on their chin. Of course, I was freaking out, but he was fine. He said it tickled."
Jennifer spent time in Las Vegas this weekend, where she attended the grand opening of the new club Hakkasan inside the MGM Grand hotel with her ex-husband Marc and her boyfriend of more than one year Casper Smart.
She said: "It's a little night off from being a mom and that's exciting. It's nice to have a little down time."
The former couple have stayed friends since their split in 2011, with Marc recently parting ways with his girlfriend Chloe Green.
The 44-year-old star is said to have ended his relationship with the Topshop heiress despite her already spending a lot of time with his five children.
An insider previously said: "It seems to be Marc's decision to end it. She's already moved her stuff from his house in Miami and has gone away with friends to get over it.
"Things happened very quickly between them -- and she'd spent a lot of time with his children."
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