Ashlee Simpson's Son Bronx Is So Grown Up -- See the Sweet Christmas Pics!

Ashlee Simpson at 2017 American Music Awards
Neilson Barnard/Getty Images

Reese Witherspoon also showed off her adorable brood over the holidays -- and they're all so cute!

Ashlee Simpson-Ross' son is so grown up!

On Tuesday, the 33-year-old singer shared photos from her family's Christmas celebration. A sweet group shot included her husband, Evan Ross, their daughter, 2-year-old Jagger, and Ashlee's son, 9-year-old Bronx, whom she shares with her ex-husband, Pete Wentz.

A couple of days earlier on Christmas Eve, she snapped a pic with Bronx, and her caption said exactly what we were thinking. "Christmas with my not so little one ??❤️??," she wrote.

Ashlee's big sis, Jessica Simpson, posted an equally festive of Bronx with her daughter, Maxi Drew, earlier in the week, which she appropriately captioned, "Just 'Cuz."

But your heart will really melt when you see the adorable video of Jagger telling Santa that she'll miss him:

Apparently, she's all about making us coo, because earlier in the month, Ashlee documented Jagger's trip to the Happy Place pop-up in Los Angeles, and the toddler looked pretty darn cute in the palm tree installation.

Ashlee isn't the only one sharing pics of her not-so-little kids. Reese Witherspoon also showed off her gorgeous fam on social media over the holidays.

The 41-year-old actress' three kids -- 18-year-old daughter Ava and 14-year-old son Deacon, whom she shares with ex-husband Ryan Phillippe, and 5-year-old Tennessee, her son with husband Jim Toth -- posed with two of their family members on a couch in front of the Christmas tree. 

The second pic in the Instagram post is just of Reese and Ava, and they seriously look like doppelgangers with their blonde hair, crimson lips and red dresses.

Can you believe how alike they look?!

For even more festive holiday photos, click through the gallery below.