Does my communication with my cousins constitute disobedience to my mother, who forbade me from it? And is the action of my uncles selling the house that my grandfather willed to my father considered religious injustice to my father in the inheritance, even though the house was not registered in his name?

The preponderant opinion is that the kin whose ties are obligatory to maintain are relatives with whom there is a blood kinship, such as brothers and sisters, paternal uncles and aunts, maternal uncles and aunts. Others, like the children of paternal and maternal uncles, are recommended to maintain ties with. There is no harm in maintaining ties with cousins without the mother's knowledge, and this does not constitute disobedience to her. If the donor dies before the donee takes possession of the gifted item, the gift becomes void, and the gifted item becomes part of the inheritance to be distributed among the heirs.