Went outside of my house, where my dog was sitting unmovable (on a cobblestone block). Placed some cobblestone, and dark oak plank blocks (outside), ignited the dark oak planks. Suddenly my dog was sitting on one of the cobblestone blocks outside, far away from where i put him. I went back to my house, where the same blocks that i ignited (dark oak plank), were on fire for no reason. I can only assume that it was because of the ones I ignited outside, and that it spred to them because of a bug.