Here's an explanation:
A few days earlier your Mum and Dad were playing chess at around lunch time. They finished the game, packed up and headed to the kitchen to make a cheese sandwich. Your Dad put the chess set on the kitchen counter and set about making the sandwich. It was a bit warm, so he took off his jumper. As he pulled it over his head, it snagged on the knife he was holding to cut the cheese. Annoyed, he pulls some thread out the jumper, flicks it away and puts the jumper on top of the chess set. Your Mum comes in, sees the jumper, and picks it up. She scolds your Dad then puts it down again. She didn't know the chess set was underneath the jumper, so she pushed the lot to one side, then sat down at the counter to eat her sandwich. Doing so left the chess set precariously close to the edge. They ate their sandwiches then left the room. On the way out your Mum picks up the jumper so as to fix it, leaving the chess set perilously close to the edge.
A few hours later, when everyone is asleep, a mouse climbed the counter to get the cheese crumbs. The thread your father previously flicked away tangles around its front and rear left paws. Panicked, it runs around in circles until it happens upon your chess box. Running at speed, and without due care to its surroundings, it knocks the set off the counter and onto the floor. Still panicking, the mouse carries on running and falls onto the floor, on top of the chess pieces. It falls on to the Queen, inadvertently wrapping a small amount of thread around the piece. The mouse then scurries into a small hole.
Several years earlier, a jumper maker was making a jumper when he fell asleep on the job. He was tired, he'd been up all night partaking in his hobby. He liked to make paper mache owls. He was good at it. He'd cover them with real feathers, but it didn't really satisfy his appetite. He wanted his owls to be more life like! One day, he had the idea to fill the owl with iron filings. He did this hoping that if he held a magnet to the feathers they would ruffle, and it would look *********** awesome. He spent all night doing it, and got iron filings everywhere! It didn't work. So he went to work, dejected, with no sleep and no shower. As he fell asleep over the jumper he was making, his head dropped into the jumper making machine. He died instantly, unfulfilled, but also passed a lot of iron filings from his hair into the machine.
Blah, blah, blah. Your Dad bought a jumper from that machine. It wasn't haunted by the jumper maker, but it did have a lot of tiny flecks of iron in it. Almost every thread had some on it, including the thread that was now wrapped around your sister's Queen.
Unbeknownst to your sister, the very same day she played chess with your brother, the neighbour had built a very powerful electromagnet. He turned it on briefly, but it pulled his glasses straight from his face. He turned off the machine (just after the Queen moved for the first time). He looked around for his glasses, but he couldn't find them. Great idea! He thought. If I turn it on again, the glasses will fly to the magnet! Problem solved! So he turned it back on. The glasses did indeed fly to the machine, but he was in between the two objects. The glasses struck him in the heel, causing him to fall forwards onto his magnet. He pushed it to the right, causing everything that was being magnetised to also lurch right with it. This was only very briefly though, as the magnet fell to the floor and broke. He died too, somehow.
There you go. Easy. The point, of course, is that there are infinite unknown possibilities that could cause movement. Only one is telekinesis. And that's most unlikely of all of them.
