Kingston, 16, has been in a relationship with Lola Albert for two years and it appears the sweethearts are more in love than ever.
The teen proved to be quite the gentleman as he shared a photo with Lola on Instagram, alongside a public love letter.
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"Wow… how lucky I am to be able to have someone as beautiful and kind by my side in this life," he wrote. "You make life brilliant. I love spending my time with you, I love our lunches, our karaoke nights, the movie marathons that we never follow through with.
"You’re my everything, and I love you sooo much! So happy anniversary to us, my love, and here’s to many more wonderful years spent together."
His famous mom was one of the first to comment and wrote: "Congrats babies," along with a red heart emoji.
Gwen and Gavin's son Kingston celebrated his two-year anniversary with his girlfriend
Gavin's sister, Daisy Lowe, also chimed in and added: "Happiest anniversary cuties," as many more sent their congratulations.
Lola had some sweet words of her own and dedicated a post to Kingston on social media too. Alongside a selfie with her boyfriend, she said: "Kingston, you are my world. Thank you for being my person. You have made me the happiest girl. Happy anniversary, i love you forever."
Kingston celebrated his 16th birthday earlier this year and fans couldn't believe where the time had gone.
Gwen - who is married to Blake Shelton - shares her three sons with ex Gavin Rossdale
Despite his parent's divorce Kingston has a very special bond with both his mom and dad and paid tribute to his mom on International Women's Day.
He declared his love for her in a cute snap he shared on social media which showed mother and son cuddled up together.
The teenager sweetly captioned the picture: "Happy women's day to my mum @gwenstefani I love you." Gwen was quick to repost the heart-warming photo on her Instagram Stories and thanked her "baby" for the sweet words. "Thank you puppy, I love my baby," she said.
Gavin also adores being a dad to his lookalike son and Zuma and Apollo too. "My kids are really funny and cool, and we have such a good time together,” he said. "But I constantly strive to be a better father. I am lucky that my life is so great."
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