Disposable diapers aren't bad for all babies or toddlers.
But some toddlers and babies can have an allergic reaction to the chemicals and materials used in the disposable diapers.
It depends on the child whether the disposable diaper will be bad for the baby or toddler.
A lot of babies and toddlers wear nothing but disposable diapers and are just fine while others will get rashes and chemical burns from the diapers.