How is the estate of a man who died leaving a wife and three sons (a son and two daughters from his wife, and a son from another wife whom he divorced) to be distributed?

If the heirs are the wife and four children (one daughter and three sons), then the wife inherits one-eighth due to the presence of a lineal descendant, based on the Almighty's saying: "But if you have a child, then for them [the wives] is one eighth of what you leave." The remainder, after the wife's share, is distributed among the four children, with the male receiving the equivalent of the share of two females, based on the Almighty's saying: "Allah instructs you concerning your children: for the male, what is equal to the share of two females." As for the divorced wife, she does not inherit if her waiting period ('iddah) has expired before the death, or if she was irrevocably divorced (talaq bain). However, if her husband dies while she is in the waiting period of a revocable divorce (talaq raj'i), she shares the one-eighth with any other wife. It is advisable to refer matters of inheritance to the Sharia courts.