Are there any rules in inheritance concerning adopted children?
Adopted children are not blood related to those who have adopted them. Hence, they cannot be considered as one’s own children. It is for this reason, they will not inherit from those who adopted them.
It is however, permissible for their guardians to give gifts to them while they (the guardians) are alive, and they can also make a will for them to the extent of one third of what is left as inheritance.
And Allah knows best.
Mufti Waseem Khan