2495. The child's mother is the best person to suckle a child. It is better that she does not claim any award from her husband for suckling the child, although it is good that he should reward her for that. However, if the mother demands more payment for suckling than a wet-nurse, her husband can entrust the child to the wet-nurse.
2496. It is recommended that the wet-nurse, whose services are obtained for a child, should be Shia Ithna-Asheri, sane, chaste, and good looking; and it is Makrooh for a wet-nurse to be a non-Shia Ithna-Asheri or ugly, ill-humoured or illegitimate. It is also Makrooh to entrust the child to a wet-nurse who has given birth to an illegitimate child.
Miscellaneous rules regarding suckling a child
2497. It is recommended that a woman avoids suckling any and every child, because it is possible that she may forget as to which of them she has suckled, and later the two persons, who are Mahram to each other, may contract marriage.
2499. It is recommended, if possible, that a child is suckled for full two years.