A childhood belief about bathrooms

when i was younger i used to always over fill the bath and sink, often flooding the bathroom. so my mum told me that there was a mouse that lived in the over flow hole, and if i over filled the bath/sink i would drown the mouse. i believed her until i was about 11, when her and my sister were reminiscing, and laughing about the fact i belived her. if i hadnt caught them, i probably would still believe them to this day!
the other stupid idea that was put into my head when i was little, was that i thought that when i flushed the toilet, something could come out of it and get me, but only when i flushed at night. my way of escaping this was to put the toilet lid down, hold the pully light switch at the same time as the flushing handle, flush, run out of the bathroom as fast as i could until i ran out of light switch cord and pull it to turn it off at the last minute! if anything it kept me fit.