Ryan Gosling and Eva Mendes celebrate daughter Esmeralda's 1st birthday with a low-key party for family and friends Credit: Sonia Recchia/Getty Images

Let them eat cake! Ryan Gosling and Eva Mendes celebrated a major milestone in daughter Esmeralda's life this past weekend: her 1st birthday!

The proud parents feted their daughter in atypical Hollywood fashion, at a small bash for friends and family. An eyewitness tells Us Weekly there were only about 20 people on the guest list, many of whom were from Mendes' large brood.

"It was a quiet and casual party, not the typical celebrity 1st birthday blowout with vendors and other celebrity guests," the onlooker says. "It looked like it was just their simple style and more about family and close friends coming together to celebrate Esmeralda."

Indeed, the Drive actor, 34, and the Place Beyond the Pines actress, 41, relied mostly on loved ones to help plan the low-key affair. According to the source, Gosling's sister brought a homemade birthday cake, and Mendes' mom and sister arrived early to set up.

"Some people brought wrapped gifts, including clothes and toys," the eyewitness tells Us. "One guest arrived carrying a rocking horse, and another had colorful plastic balls to fill a ball pit."

Mendes recently joked that her family tends to "take over" when they visit. "They take my baby! They start cleaning everything," she told Glam Belleza Latina. "They sound like a bunch of hyenas, yelling in Spanish, English, Spanglish. They sing [my daughter] all these Cuban nursery songs that I forgot my mom used to know...I'm so happy that my little girl gets to grow up with this."

As previously reported, the Hitch star gave birth to Esmeralda on Sept. 12, 2014. "Ryan is thrilled it's a little girl," a source told Us at the time.

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