Mother died leaving 3 daughters who are adults and are married, one brother and one sister, Father died 40 years ago. Please explain who has share in property of mother and how much?

All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad is His slave and Messenger. We ask Allaah to exalt his mention as well as that of his family and all his companions.

If the matter is as you mentioned in the question that the mother died and left three daughters, one brother and one sister, and did not leave any other heir, then the inheritance should be divided as follows:

The girls will get two-thirds of inheritance which they should divide equally between them, as Allaah Says (what means): {But if there are [only] daughters, two or more, for them is two thirds of the inheritance.}[Quran 4:11]. The remainder, which is a third, will be divided among the brother and the sister, the brother a share double that of the female. Allaah Says (what means): {If there are brothers and sisters, the male will have twice the share of the female.}[Quran 4:176]. This is in case the brother and the sister are from the same father and mother, or both are of from the same father. But if one is from the same father and mother and the other is from the father's side only, then the brother or the sister who is from the same father and mother will take the remaining third and the brother or sister from the father's side only, will not get anything. The same thing applies if one of them is from the mother's side only; he/she will not inherit anything due to the existence of the sisters.

Finally, we advise you to take the matter to the nearest Islamic centre so that they would study the matter and make sure that there is no other heir whom the questioner did not know that he was an heir, as it might be that there is another heir who could not be identified except after investigating and after asking all the heirs. 

Allaah Knows best.