A diaper rash is a skin problem that develops in the area beneath an infant's diaper. CAUSES  Diaper rashes are common in babies between 4 and 15 months old. they may be noticed more when babies begin to eat solid foods. diaper rashes caused by infection with a yeast (fungus) called candida are very common in children. Candida grows best in warm, moist places, such as under diapers. symptom  Bright red rash that gets bigger. very red and scaly areas on the scrotum and penis in boys. red or scaly areas on the labia and vagina in girls pimples blisters ulcers large bumps or sores filled with pus. Medical advice  The best treatment for a  diaper rash is to keep the diaper area clean and dry. this also helps prevent new diapers wash the area with mild soap and dry thoroughly lay your baby on a towel without a diaper.  Whenever possible. the more time the baby can be kept out of a diaper, the better. Expose diaper rash to air as much as possible change your baby's diaper rash to ai