I always tell parents to be careful about what they put in their baby's ear

Most of the time, any fluid leaking out of an ear is ear wax. A ruptured eardrum can cause a white, slightly bloody, or yellow discharge from the ear. This could have been caused by
Injury from a blow to the head, foreign object, very loud noises, or sudden pressure changes (such as in airplanes), Inserting cotton-tipped swabs or other small objects into the ear or Middle ear infection. so you'll need to see a doctor