No, I searched and couldn't find it. But I believe I remember it from somewhere, so it's not just C&C who does.Nothing about William (or her) falling up hill though, right? As was stated in the original post. Which is why I asked for a link.
"In two statements made to police after William’s disappearance, the foster mother said on the morning in question she slipped and grazed her right hand while playing with William outside the Benaroon Drive house."
Edit: Not about William falling or being involved in FFC's fall, though.