The sweet photo included the newest family member, 3-week-old Ziggy Blu

By Jen Juneau
November 20, 2020 11:46 AM
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Happy birthday, Bronx Mowgli!

Ashlee Simpson Ross' oldest child turned 12 Friday, ringing in the last of his preteen years amid sweet well-wishes from his mom and stepdad Evan Ross.

In honor of the occasion, both Simpson Ross, 36, and Ross shared the first photo to social media of their new family of five, which also includes 3-week-old son Ziggy Blu and daughter Jagger Snow, 5.

"Happy Birthday Bronx!!" Simpson Ross wrote, addressing her son, whom she shares with ex-husband Pete Wentz. "You are the coolest, kindest, deep, soulful kid (almost teen) and I am so lucky to be your mom! We love you so much! Happy twelfth 🥳"

Credit: Erik Melvin

"Happy birthday KING BRONX," added Ross, 32, in the caption on his post.

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The couple welcomed Ziggy, their second child together, on Oct. 29 — announcing the happy news on Instagram two days later.

"10-29-2020 Ziggy Blu Ross. Our sweet boy has arrived! I'm over the MOON we are so Blessed!" the new mom captioned the photo of the newborn at the time.

"I'm in heaven," Ross wrote along with a similar caption and same photo of their newborn.

Earlier this month, the "Pieces of Me" singer shared the first sibling photo, featuring Bronx cradling his new baby brother as Jagger sported a giant smile, standing in front of the pair.

RELATED VIDEO: Ashlee Simpson Shares First Photo of Children Bronx and Jagger with Their Newborn Sibling Ziggy

Ziggy's arrival marks the newest addition to Ross and Simpson Ross' blended family that also includes Wentz and longtime girlfriend Meagan Camper's two children: daughter Marvel Jane, 2½, and son Saint Laszlo, 6.

During a September 2018 episode of Watch What Happens Live, Ross opened up about the relationship between himself and Wentz, 41, when it comes to co-parenting Bronx.

"I grew up with a big family," said the actor and musician, who is the son of legendary songstress Diana Ross. "I think it's a beautiful thing. … My relationship with Pete has been amazing. He's an amazing father. He knows I love his son very much, but it's his son."

"I'm like, 'Thank you, God,' " Simpson Ross chimed in about the twosome's amicable dynamic, joking, "God looked at me one day and shined."