A Muslim brother passed away and is survived by a wife, two daughters, two full sisters, one brother from father, one sister from father and one sister by mother.
His father and mother were never married.
بسم الله الرحمن الرحيم
This estate of the deceased would be divided into sixteen portions. The only inheritors would be the wife of the deceased and his two daughters. The wife would receive two portions and each daughter would receive seven portions.
The reason being is that a marriage was never contracted between the biological parents, as a result there would not be any Nasab (linage) between the deceased and his biological father. Even though he may be his biological father the Shariah does not regard him as his real father. Rather the linage of the deceased would be connected to his mother. Subsequently the offsprings of his biological father (biological paternal siblings) would not be in any relation to him (i.e. deceased). Hence they (biological paternal siblings) would not be considered his heirs. Therefore the “brother from the father” and “sister from the father” mentioned in the question are not the heirs of the deceased.
As for his “two full sisters”, they would only be regarded as his maternal sisters and not “full sisters” as discussed above. Therefore, he would have three maternal sisters as his heirs. They however, would not inherit because maternal sisters do not inherit in the presence of the daughter/s of the deceased.
NB: This answer is specific to the details stated in the question.
And Allah Ta’āla Knows Best
Mufti Kaleem Muhammad
Darul Iftaa, Jaamia Madinatul Uloom
Trinidad, West Indies