Last year I carried a Travelon small messenger bag as my purse for our trip. Of course never thinking that there were magnets in there to keep flap closed. Our tickets/room key kept getting demagnetized !!! Help, what kind of small across the body bag do you carry. I have a four year old, I will just be carrying wallet, sunscreen, handiwipes, chapstick and camera and small first aid kit. Nothing to big or to small, Any Suggestions??