Gwen Stefani's rarely-seen son looks so happy as he receives a sweet celebrity kiss
Gwen Stefani's middle son looked on cloud nine in an adorable snapshot his famous mom posted on Instagram on Wednesday.The mom-of-three, who shares her sons, Apollo, seven, Zuma, 13, and Kingston, 15, with her ex-husband, Gavin Rossdale, took the opportunity to put Zuma in the spotlight.MORE: Gwen Stefani and Blake Shelton reveal new Christmas family traditions The youngster rarely features on Gwen's social media, so it was a welcome treat for fans of the family. WATCH: Gwen Stefani shares glimpse inside stunning new marital mansion In the image, Zuma was beaming from ear to ear and had his eyes closed in joy as Ariana Grande planted a kiss on his cheek.The lad looked overjoyed at the moment captured on the set of The Voice, where Gwen's