Gwen Stefani's son Kingston marked his milestone 16th birthday earlier in the week, and his family members couldn't have been more thrilled.MORE: Gavin Rossdale's daughter Daisy Lowe shows support for famous dad as he shares exciting newsALSO: HELLO! launches Jubilee T-shirt collection to celebrate Queen Elizabeth in styleBeaming with pride, of course, was his father Gavin Rossdale, Gwen's former husband, and he took to social media with an emotional tribute.VIDEO: Gwen Stefani's son is hilarious as he reveals his mum's dirty habitThe musician shared a snapshot of his older son all grown up and wrote: "Happy birthday sweet 16 Kingston you changed my life forever and I will never be the same again. "You are a force of light. You have bloomed like an ancient spirit.