Maria Dakake answers the questions
Q: Polygamy was based on what Muhammad did, why he had 8 wives at one time?
Q: How about concubinage among polygamy, how is that rationalized?
Q: Is it okay to sell Concubine in Islam?
Q: Can they sell her once they have a child? Marrying a slave men.
Q:Are children of the concubine have equal rights as of children of the wife? Dakake also talks about children rights from concubine and slave rights in Islam at Dar al Islam Teachers institute of Abiquiu, NM.