Sitting with her on the stairs refers to his story that he was at a party at the Ramseys on the 23 of Dec. at which he showed her coin tricks and gained her trust. It isn't refering to the night of the murder.
Thanks. If the head trauma is as described by the pathologists, I think we've got a "hum-dinger" of oddities going on that night. The Ramseys couldn't have been 'luckier' without an intruder dropping by. I think it is beyond reasonable belief that we can assume that BOTH an intruder dropped by and such a rare head trauma just happened to occur at about the same time the intruder killed her. That's fantastic.