My 18 month old dd has had blood stained bed sheets the past four mornings in a row. Blood clearly coming from mouth as drool shaped patches all over, but no evidence on dd herself. Took her to walk-in yesterday who were clearly shocked by sheets, but as she was well in herself said they weren't concerned, but didn't know why it was happening. Can see canines are coming through but have never heard of babies bleeding whilst teething. Only happens when she's sleeping...help!