Simon: What Happened? Judge David Just Can't Resist Joining That Little Boy On Stage?

<p id="watch-headline-title" class="yt"><span id="eow-title" class="watch-title long-title yt-uix-expander-head" title="David's mini-me singer Ellis Chick swings through his audition | Britain's Got Talent 2014" dir="ltr">David's mini-me singer Ellis Chick swings through his audition | Britain's Got Talent 2014</span></p>