Jennifer Garner's Costume Embarrasses Her Son at His 7th Birthday Party

Jennifer Garner
Presley Ann/FilmMagic

Samuel did not appreciate his mom's getup!

Jennifer Garner's birthday surprise for her son wasn't received quite as she expected.

The 46-year-old actress took to Instagram on Thursday to share a hilarious snap from her son Samuel's 7th birthday party. The tot's bash was How to Train Your Dragon themed, even featuring a cake with the movie's beloved dragon, Toothless.

As Garner excitedly brought out the cool cake, she surprised her son, whom she shares with ex-husband Ben Affleck, by donning the costume of the flick's female viking warrior, Astrid. Wearing fur boots and a matching shawl, along with some leather armor and blue face paint, Garner was the spitting image of Astrid, who was voiced by America Ferrera in the movie. 

"Well, guess what. It turns out seven is the age my kid stops thinking it’s cool when I dress up for the party," Garner quipped before adding hashtags reading "youngest child," "first eye roll," and "anyone need an Astrid?"

Though Samuel may not have approved of his mom's display, Ferrera was totally on board with Garner's incredible costume.

"Ahhhh!!!! Yeeeeessss!!! AMAZING @jennifergarner as ASTRID!!" Ferrera wrote on her Instagram Story. 

Instagram

In addition to Samuel, Garner and Affleck share two daughters, Violet, 13, and Seraphina, 10. Despite still co-parenting, the formerly married couple have each moved on romantically; Garner with boyfriend John Miller, and Affleck with his potentially former ex, Lindsay Shookus.

A source recently told ET that Garner and Miller are in "the honeymoon phase of their relationship," and spend a lot of time with each other's kids -- Miller has two from a previous relationship -- despite initially wanting to "take it slow."

"John's been at their Palisades house so much lately," the source said. "They all [Miller, Garner and their kids] stay up late playing board games." 

"While they've spoken about a future together, neither of them are ready to plan a wedding or get engaged," the source added. "Jen has no interest in jumping into marriage quickly. She only just solidified her divorce so right now she just loves all their time together.”'

Watch the video below for more on the couple:

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