Is it permissible for a mother to register her share of the house in the name of one of her children without the knowledge of their other siblings?

The fundamental principle is the obligation to be just among children in gifting, and it is not permissible to favor some of them with a gift without a legitimate reason. This is achieved either by returning the excess or by completing the share of the other. Jurists have used the hadith (definition) of Nu'man ibn Bashir as evidence: "Fear Allah and be just among your children," which described favoritism as injustice and commanded its reversal. The mother is like the father in the obligation of being just among children and in the consequences of favoring one of them, such as envy and animosity. It is important to note that merely writing a property in the name of the donee for them to acquire it after the death of the donor, without actual possession or the ability to dispose of it during the donor's lifetime, does not constitute a valid gift according to Sharia (definition). Rather, it is considered like a will, and a will for an heir is not enforceable except with the permission of the rest of the heirs.