Simpson shares Bronx with ex Pete Wentz, and is mom to daughter Jagger, 9, and son Ziggy, 3
Ashlee Simpson Ross' son is officially 16!
On Wednesday, Nov. 20, the "Pieces of Me" singer, 40, shared a series of photos on her Instagram as she celebrated her son Bronx's 16th birthday. In one photo, the mother-son duo poses under a canopy of lights, with the teenager standing a full head taller than his mom, who carries a bouquet of roses.
Simpson Ross also included a few throwback photos from when she was pregnant with Bronx and snaps of him as a child, as well as pictures of Bronx with his younger siblings. "Being your mom has been the greatest joy of my life. You are my rock my soul. My ride or die. You have been the greatest blessing in life that I could have ever dreamed of," Simpson Ross sweetly wrote in her caption.
"I would not be me without you. Thank you for choosing me to be a mom, and YOUR mom. You are so calm, consistent, brilliant, loving, kind hearted, thoughtful, funny, mysterious, and incredibly awesome. I thank God every day that I get to be your mom."
"You are a true gift to this universe and I'm so lucky you are my very grown, and cool baby... happy 16th birthday. I love you. Also you were born to this song. Thank you for making me the luckiest," she ended her caption.
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Related: Ashlee Simpson Ross Takes Daughter Jagger, 9, to See Olivia Rodrigo in Concert: 'What a Fun Time'
"Nothing cuter than taking the girls to see @oliviarodrigo what a fun time ❤️," Ashlee captioned the carousel, which featured a photo of Jagger posing with her friends, a snapshot of the group posing with the "drivers license" singer and a video of the little girl and her friends singing along while watching Rodrigo, 21, perform onstage.
In June, Simpson Ross spoke with PEOPLE about how she juggles parenting three kids of different ages, noting that she's been able to rely on past experience to help her smaller kids.
"I have every different age. Every time I can be like, 'I've been there, we've been there. Now it's my 3-year-old,' " Simpson Ross shared. "But it's amazing. Everyone is their own individual self and has their own personality and it's really nice."
"Everyone's going through something different. My oldest son's going to be 16, my daughter is 8. She's all into the music and my old music, Olivia Rodrigo, all the things. And then my 3-year-old's in there dancing and being hilarious and entertaining himself. It really actually works out. It's a nice balance."