Inheritance in Islam for sons and daughters is under joint residuary. Muslim Sons under Islami law receive a Joint Residuary with Daughters; otherwise, they receive residue as an independent. Sons get double the share of Daughters under Joint Residuary as stated in the Holy Quran, 4:11.
Sons do not receive fixed or prescribed division shares. In the presence of a Son, the daughter's fixed shares can vary in certain conditions due to the increase or decrease to match the proportion of males getting twice the share of females. However, the residue is not left to distribute for the property under Awal (or Aul) scenario. Radd, on the other hand, is distributed to Residuary.
The Father cannot restrict children receiving share in Islam and must follow Faraid as stipulated in the Holy Quran, 4:11.
There is certain Hajb (i.e., blocking or exclusion) rules are applicable for descendants. Sons block Sons of Sons (how low soever) and also block siblings and their descendants. Sons also exclude Granddaughters (how low soever).
Sons receive from their parents (i.e., Husband or Wife) only if their parents were married Islamically (i.e., Nikah); otherwise, they are not eligible under Islamic law. By the same token, if they married Islamically but do not have registered marriage or other evidence of marriage, then spouse and/or children cannot receive legally.
An estate from a Muslim son can be inherited by his wife, children (or grandchildren), and parents (or grandparents) as primary heirs. These are the legal heirs after the death of a married son in Islam. Refer to "Islamic inheritance sharers and residuary" to learn more.
An unborn child within its mother's womb can receive, regarded as born in a viable state. An embryo is considered a living individual, leading to an immediate vesting of property rights in the child. However, should the child within the womb not survive birth, the previously vested share is revoked and treated as if the heir (within the womb) never existed.
Sons also can own lifetime gifts (i.e., Hiba) from their parents without any classification or restrictions, but all children should be treated equally for lifetime gifts as stated in the Book of Hadith, Bulugh al-Maram, Book 7, Hadith 928; "My father went then to the Prophet (Sallallahu Alayhi Wasallam) to call him as a witness to my Sadaqah (i.e., gift), and he asked, "Have you done the same with all your children?" He replied, "No." He said, "Fear Allah and treat your children equally." My father then returned and took back that gift." If you want to give more to one child (or children) than the rest child (or children), please consult a knowledgeable Sunni Islamic scholar.
In Islamic practice, there are fair deals between men and women. Upon the passing of their predecessor, both female and male offspring have the legal status of successive heirs. However, the portion allocated to a female heir is often half what is granted to male heirs. This distinction originates from the Islamic legal framework, where a woman receives mehr (dowry) and ongoing support from her husband upon marriage, while males solely rely on ancestral property for succession. Moreover, males are entrusted with the responsibility of providing for their spouse and children.