Hello Madam thanks for the concern.
skin color is a geneticaly/hereditary related thing which cant be altered by any drugs or creams or facials. these may have temporary effect with side effects of darkening the skin.As you child is small dont try any thing on her baby soft skin.
there are no foods that reduce melanin
.only thing is to have balanced diet.your baby is wheatish not black. so dont worry.take care.