'Carry You' singer JJ, who welcomed Princeton last November with model girlfriend Caterina Lopez, is currently enjoying a family trip to Cornwall.
In a photo posted to Twitter yesterday (17 March), four-month-old Princeton is seen sitting beside his father on a blue blanket looking out on to the coast.
Captioning the snap, JJ said: "Princeton's first day at the Beach. #FatherAndSonTime."
In similar photos posted to Instagram, Caterina said: "Showing Princeton the world at a young age."
Princeton is growing up to be one handsome baby boy, as last week Caterina shared an adorable photo of him on Instagram.
In the snap, Princeton is dressed in brown trousers, a striped top and a cute blue flat cap, and looks on straight at the camera with his piercing blue eyes.
Aside from enjoying some quality family time, JJ and his bandmates George Shelley, Josh Cuthbert and Jaymi Hensley have been busy working on their upcoming second studio album.
Their self-titled debut album was a top 10 hit, having peaked at number six in the UK music charts following its release in November last year.
For their new album, the boys recently told Capital FM that their songs will have a "country twist" to it. George added: "If you can imagine Taylor Swift meets Little Mix meets Union J."
Union J rose to fame after starring on The X Factor in 2012, in which they were mentored by Louis Walsh. The boys finished in fourth place.
Following their success on the ITV talent show, Union J have achieved two top 10 singles, a top 10 album and have embarked on a UK headline tour.
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