Ashlee Simpson Ross Tells Waiter 'This Is My Kid' After Son Bronx, 14, Is Offered a Glass of Wine

Chris Millard/Warner Bros. Ashlee Simpson Ross

Ashlee Simpson Ross is dealing with the realities of her son growing up.

Chatting with Jennifer Hudson on her eponymous talk show this week about what it's like to have a teenage son, the "Pieces of Me" singer marveled at how her oldest, son Bronx, 14, is "so tall."

"He's like 5' 9½", he towers over me," said the singer, 38, who shares Bronx with ex Pete Wentz. "He's really chill, though, so I'm lucky for that."

"He's a good kid so far," she laughed, adding, "stay that way, bro."

After Hudson joked about her own son, 13-year-old David Daniel Otunga Jr., and his changing voice and appearance, Simpson Ross noted that Bronx's "voice is deep, he's a young man."

It appears that way to others as well, as she recalled a recent mishap that occurred during a night out at the movies with Bronx and husband Evan Ross.

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"I'm sitting next to Bronx and Evan is on [the other] side, and we're at one of those movies where they offer you wine or something, and they were like, 'Oh sir [to Bronx], would you like something?'"

Simpson Ross quickly moved to correct the waiter, saying, "He's not my friend — well he's my friend, but this is my kid, my 14-year-old son."

In addition to Bronx, Simpson Ross is also mom to son Ziggy Blu, 2, and daughter Jagger Snow, 7, with Ross.

Elsewhere in the sitdown, the "La La" singer revealed that her daughter has discovered her mom's first album and is obsessed.

Ashlee Simpson/Instagram

"My daughter, she's the one that's like, 'I want to hear mommy's music,'" she shared. "So I get to listen to it quite frequently now."

Jagger was with her mom in September, when she surprised fans with a performance of "La La" alongside Demi Lovato.

"I brought my daughter, she wore a little rock outfit," she said. "That was so much fun. It was fun to perform with Demi, I was so flattered that she sang 'La La' on tour. To get back out there and sing that with her — who I love her, her voice is so beautiful, it was just fun energy. We had a really good time together, definitely made me miss the stage and singing."