How is the inheritance divided among: a wife, one son, three daughters, and two sisters from the father's side?

If the heirs are limited to those mentioned, the wife receives one-eighth due to the existence of a direct descendant, based on the Almighty's saying: "But if you have a child, then for them is one eighth of what you leave." The remainder is divided among the son and the three daughters by way of ta'sib (agnatic inheritance), with the male receiving 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." The two paternal sisters receive nothing because they are excluded by the presence of the son. The estate is divided into forty shares: the wife receives five shares, the son fourteen shares, and each daughter seven shares. It is advisable to refer inheritance matters to Sharia courts for investigation.