Photo: Kristin Cavallari/instagramKristin Cavallariis totally dunzo being 34.TheVery Cavallaristar celebrated her 35th birthday on Wednesday, showcasing her stylish outfit on Instagram in honor of her big day as she posed next to a simple yet chic display of gold balloons that spelled out “Happy Birthday.“TheLaguna Beachalum looked sleek and ready for a night on the town in an all-black getup, which consisted of curve-hugging bottoms, a low-cut top with a sweetheart neckline, a structured blazer, and strappy sandals.The Uncommon James founder’s friends flocked to the comment section to send their best birthday wishes on her special day, including Cavallari’s formerThe HillscostarHeidi Montag, who wrote, “👏👏👏👏👏👏 Happy Birthday hot mama!!!!!!!❤️💋🥰.” Model Lily Aldridge added a chain of heart emojis.Never miss a story — sign up forPEOPLE’s free daily newsletterto stay up-to-date on the best of what PEOPLE has to offer, from juicy celebrity news to compelling human interest stories.BFF andVery CavallaricostarJustin Andersonwas also there to celebrate the momentous occasion, as heposted a videoof the reality star’s balloon decorations on his Instagram Story – including one of the balloons that fell down, making the display hilariously spell out “Happy Birth ay"Additionally, Anderson posted a picture of what appears to be Cavallari’s birthday cake on his Story, captioning the sweet snap, “happy happy to my best fren.“Justin Anderson/instagramCavallari’s birthday celebration comes just one week after she and her family, including sons Camden Jack, 9, and Jaxon Wyatt, 7, plus daughter Saylor James, 6, headed to the mountains for afun-filled ski dayon the slopes.Cavallari shares all three children with ex-husbandJay Cutler.RELATED VIDEO: Kristin Cavallari on Her Worries of Raising Kids in Spotlight: ‘I Only Care if They’re Happy’In December,a source told PEOPLEthat theBalancing in Heelsauthor and Cutler were focusing on co-parenting their children ahead of the holidays.“Kristin is looking forward to spending the holidays with the kids. They’ll be having a quiet Christmas at home in Tennessee,” the insider said.Added the source: “They’ve worked really hard to get to a good place and manage the kids and the holidays and are doing their best to keep it positive and friendly. Things have gotten better recently.”

Photo: Kristin Cavallari/instagram

Kristin Cavallari

Kristin Cavallariis totally dunzo being 34.TheVery Cavallaristar celebrated her 35th birthday on Wednesday, showcasing her stylish outfit on Instagram in honor of her big day as she posed next to a simple yet chic display of gold balloons that spelled out “Happy Birthday.“TheLaguna Beachalum looked sleek and ready for a night on the town in an all-black getup, which consisted of curve-hugging bottoms, a low-cut top with a sweetheart neckline, a structured blazer, and strappy sandals.The Uncommon James founder’s friends flocked to the comment section to send their best birthday wishes on her special day, including Cavallari’s formerThe HillscostarHeidi Montag, who wrote, “👏👏👏👏👏👏 Happy Birthday hot mama!!!!!!!❤️💋🥰.” Model Lily Aldridge added a chain of heart emojis.Never miss a story — sign up forPEOPLE’s free daily newsletterto stay up-to-date on the best of what PEOPLE has to offer, from juicy celebrity news to compelling human interest stories.BFF andVery CavallaricostarJustin Andersonwas also there to celebrate the momentous occasion, as heposted a videoof the reality star’s balloon decorations on his Instagram Story – including one of the balloons that fell down, making the display hilariously spell out “Happy Birth ay"Additionally, Anderson posted a picture of what appears to be Cavallari’s birthday cake on his Story, captioning the sweet snap, “happy happy to my best fren.“Justin Anderson/instagramCavallari’s birthday celebration comes just one week after she and her family, including sons Camden Jack, 9, and Jaxon Wyatt, 7, plus daughter Saylor James, 6, headed to the mountains for afun-filled ski dayon the slopes.Cavallari shares all three children with ex-husbandJay Cutler.RELATED VIDEO: Kristin Cavallari on Her Worries of Raising Kids in Spotlight: ‘I Only Care if They’re Happy’In December,a source told PEOPLEthat theBalancing in Heelsauthor and Cutler were focusing on co-parenting their children ahead of the holidays.“Kristin is looking forward to spending the holidays with the kids. They’ll be having a quiet Christmas at home in Tennessee,” the insider said.Added the source: “They’ve worked really hard to get to a good place and manage the kids and the holidays and are doing their best to keep it positive and friendly. Things have gotten better recently.”

Kristin Cavallariis totally dunzo being 34.

TheVery Cavallaristar celebrated her 35th birthday on Wednesday, showcasing her stylish outfit on Instagram in honor of her big day as she posed next to a simple yet chic display of gold balloons that spelled out “Happy Birthday.”

TheLaguna Beachalum looked sleek and ready for a night on the town in an all-black getup, which consisted of curve-hugging bottoms, a low-cut top with a sweetheart neckline, a structured blazer, and strappy sandals.

The Uncommon James founder’s friends flocked to the comment section to send their best birthday wishes on her special day, including Cavallari’s formerThe HillscostarHeidi Montag, who wrote, “👏👏👏👏👏👏 Happy Birthday hot mama!!!!!!!❤️💋🥰.” Model Lily Aldridge added a chain of heart emojis.

Never miss a story — sign up forPEOPLE’s free daily newsletterto stay up-to-date on the best of what PEOPLE has to offer, from juicy celebrity news to compelling human interest stories.

BFF andVery CavallaricostarJustin Andersonwas also there to celebrate the momentous occasion, as heposted a videoof the reality star’s balloon decorations on his Instagram Story – including one of the balloons that fell down, making the display hilariously spell out “Happy Birth ay”

Additionally, Anderson posted a picture of what appears to be Cavallari’s birthday cake on his Story, captioning the sweet snap, “happy happy to my best fren.”

Justin Anderson/instagram

Kristin Cavallari

Cavallari’s birthday celebration comes just one week after she and her family, including sons Camden Jack, 9, and Jaxon Wyatt, 7, plus daughter Saylor James, 6, headed to the mountains for afun-filled ski dayon the slopes.

Cavallari shares all three children with ex-husbandJay Cutler.

RELATED VIDEO: Kristin Cavallari on Her Worries of Raising Kids in Spotlight: ‘I Only Care if They’re Happy’

In December,a source told PEOPLEthat theBalancing in Heelsauthor and Cutler were focusing on co-parenting their children ahead of the holidays.

“Kristin is looking forward to spending the holidays with the kids. They’ll be having a quiet Christmas at home in Tennessee,” the insider said.

Added the source: “They’ve worked really hard to get to a good place and manage the kids and the holidays and are doing their best to keep it positive and friendly. Things have gotten better recently.”

source: people.com