Prince William’s 42nd birthday on Friday, June 21, came with a “heartfelt” photograph snapped by his wife, Catherine, Princess of Wales. The image depicted the future king and their three children having fun at the beach in May, and won raves from even the most veteran of all royal photographers. “By the looks of things, it’s going from strength to strength,” The Sun’s long-serving royal lensman Arthur Edwards told the outlet. “And, as this photo shows, the future of the royal family is in safe hands.” “You know if you’ve got a smiling and happy family every time you take a picture you’ve got …