The late Jon Pertwee told me during a BBC studio interview back in 1974 when I was President of the D.W.I.F.C. (Doctor Who International Fan Club) that his young son Sean would become Doctor Who one day and follow in his fathers footsteps. Chris Chibnall the new man taking over the reins from Steven Moffat has said that he would prefer a much younger actor to take over the roll once he takes up his new job with Doctor Who. Chris Chibnall has also hinted that Peter Capaldi will be leaving the show at the end of the 2017 series. This would be an ideal opportunity for Sean to take over the roll of Doctor Who.

 http://www.radiotimes.com/news/2015-10-05/sean-pertwee-it-would-be-an-honour-to-play-my-dads-version-of-the-doctor