It must have been McNutt or maybe Swiper

Grammie introduced Nathan and Bea to a character (from a book, I think) named McNutt. He seems to be a friendly imaginary guy who can be blamed for ... almost anything- moving things, making a mess, cleaning things up, making mysterious and otherwise unexplained noises. McNutt has been very helpful in our house. I really have enjoyed this imaginary guy. In the past, I had been doing a lot more reassuring in situations that seemed worrisome to N and B or explaining of why I had meddled with their stuff. Now, whenever there's something new or changed that might have made my slightly particular children worried or annoyed they tell me it was just "McNuckt" before I even think of what to say. A few weeks ago, Swiper was added to the characters who can make mischief in our house. It took me a while to realize that this was a character in the Dora cartoons who tries to swipe things away. So, now instead of being upset when the lego sculpture has been moved or the juice cup that was still half full is gone, we play an imaginary game together about 2 endearing and meddling characters.