Gwen Stefani gets an adorable smooch from Blake Shelton at her son Zuma's birthday bash

Gwen Stefani and Blake Shelton continue to be the cutest couple ever.

The pair showed some sweet PDA at Stefani's big bash celebrating her son Zuma's eighth birthday on Sunday, and wasn't shy about sharing the love with their fans. In one particularly squeal-worthy Snapchat shared by the No Doubt frontwoman, Shelton gives her a big kiss on the cheek.

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WATCH: Gwen Stefani and Concert Fans Sing 'Happy Birthday' to Her 8-Year-Old Son Zuma

Shelton also kept his arm around 46-year-old Stefani, as the two partied with friends.

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Snapchat

Check out the 40-year-old country crooner toasting with a red solo cup!

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Snapchat

WATCH: Gwen Stefani and Blake Shelton Are the Cutest Couple Ever in Surprise Dallas Performance

The former Voice colleagues also spent time together on Saturday night, when they performed their duet "Go Ahead and Break My Heart" at the star-studded charity event, Apollo in the Hamptons, at The Creeks in New York. Stefani and Shelton couldn't look happier snuggled up at dinner, where they were joined by Pharrell Williams, Jennifer Lopez, Katie Holmes, Ciara, and Jon Bon Jovi.

Watch the video below for more on the celeb-packed fundraiser.