While my eldest sun was a year or so old, he had a rattle with a big sucker so you could stick it to his high chair. Like many fathers, I once stuck it to my forehead, couldn't get it off and ended up with a perfectly circular bruise about 10cm across right in the middle of my forehead.

I had to go to my doctor (NOT the one mentioned above!) for some other reason later in the week and, after describing all these other symptoms in detail the doctor ignored them completely and asked if I had ever considered plastic surgery 'for the birthmark'. I can't say it inspired much confidence. Do you get perfectly circular birthmarks?

(I gather a couple of doctors also stuck these toys to their head a year or two later, and published an article in 'The Lancet' about it!)