Congratulations are in order for Ashlee Simpson Ross, who welcomed her third child, Ziggy Blu Ross, on Oct. 29, 2020. The "Pieces of Me" singer announced the happy news on Saturday with an adorable snap of her bundle of joy. 

Watch TODAY All Day! Get the best news, information and inspiration from TODAY, all day long. She wrote in the caption, "Ziggy Blu Ross. Our sweet boy has arrived! I'm over the MOON! We are so blessed." This is Simpson Ross' second child with husband Evan Ross, whose mother is Motown legend and Grammy-winning singer Diana Ross. 

Their first child, daughter Jagger Snow Ross, is five years old. Simpson Ross is also the mother of 11-year-old son Bronx Wentz, who she shares with ex-husband and Fall Out Boy bassist Pete Wentz. The 36-year-old mom first shared the news of her pregnancy in April, when she posted a photo of herself holding up a positive pregnancy test on Instagram. 

"We are pregnant and we are so excited to share it with everyone," she wrote at the time. In the caption, she also urged fans and followers to support March of Dimes' Mom and Baby COVID-19 Intervention and Support Fund, which helps "moms and babies get the care they need now and in the future." 

 In September, Simpson Ross celebrated her pregnancy during a sweet baby shower and posed for photos with several generations of her family, including daughter Jagger, sister Jessica Simpson, nieces Birdie Mae and Maxwell Drew Johnson, and mother Tina Simpson. 

"I’m so grateful to be with my family as we get ready for my baby boy! Not long now!" Simpson wrote in an Instagram caption. In 2016, the singer opened up to TODAY Parents about motherhood and offered advice to other moms. 

 "My advice to other moms would be to take every day one day at a time, especially with your kids so you can be present in each moment," Simpson Ross said. "Sometimes it's hard because life gets chaotic. 

It's about learning to take a deep breath, whether it's while you're cleaning or while your children are taking a nap, just doing a little something to relax and be able to focus."

Ashlee Simpson Ross and Evan Ross' daughter wasn't initially into the idea of having a baby brother. On Wednesday's episode of SiriusXM's The Jess Cagle Show, Ross, 32, opened up about how the couple's 5-year-old daughter Jagger Snow has handled becoming a big sister to their son Ziggy Blu, who was born in October. 

"Well, she loves the baby but when she found out that it was a boy, at first, she was super, super mad," Ross said. "She was furious." 

"We did a gender reveal with the whole family on Zoom and I could see her like, on my side and it was like, she broke down," he added, playfully recreating her reaction. "[She] was like, so upset."

Fortunately, everything changed after Jagger met her little brother. "Now, she's a great big sister. She kisses him probably every five seconds," Ross says of his daughter. 

 Jagger has also gotten help from 12-year-old brother Bronx Mowgli, whom Simpson Ross shares with ex-husband Pete Wentz. "Bronx, their older brother, is the most chill guy. He's so well-grounded and takes care of both of them so well," he explained. 

"Jagger's become this great big sister. He helps her with it too so she doesn't feel like she's having to share the attention."

Since welcoming their son, Ross and his wife have posted several cute photos of their happy family on social media. 

The "Pieces of Me" singer, 36, shared the first sibling photo of her three kids in November, just days after the newborn's arrival. For Bronx's birthday later in November, the proud mom debuted the first photo of their new family of five for the occasion. "Happy Birthday Bronx!!" Simpson Ross wrote in the affectionate post. 

"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" Since then, Ziggy has also gotten a chance to meet some other very important family members, including aunt Jessica Simpson. 

Earlier this month, Simpson shared an adorable snapshot of her youngest child, daughter Birdie Mae, 22 months, curling up beside her young cousin. "#ZIGGYBLU + #BIRDIEMAE," Jessica, 40, captioned the black-and-white photo of the two youngsters peering into the camera.

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