David followed suit, posting a selfie that was snapped during a hike.
"Happy 15th Birthday big boy," he wrote. "Fine young man growing up to be a fine young gentleman but has only beaten his dad at tennis just the once ? so far but maybe now he is 15 that's gonna change ?..."
"Happy Birthday big boy," he added. 'We love you... @romeobeckham @victoriabeckham ❤️"