Can a person be disinherited from their share for family disputes or disobedience?

No — a fixed Quranic heir (such as a child, spouse, or parent) cannot be disinherited from their basic entitled share simply because of a family dispute, disobedience, estrangement, or a parent's personal displeasure; the Quranic shares are a divinely fixed right, not a reward for good behavior that a family member can revoke. This surprises many people, but it is a deliberate feature of the system — it protects heirs, including "difficult" or estranged ones, from being cut out arbitrarily.

What a person can do is use their discretionary one-third wasiyyah (see Q3) to favor certain non-heirs, give lifetime gifts (hiba) to whomever they choose while alive (though scholars caution these should be done fairly among children to avoid future disputes), or simply choose not to leave anything beyond the fixed shares to someone. The one narrow exception recognized in fiqh is that a person who unlawfully kills the one they would inherit from is barred from inheriting from that person — but ordinary disobedience, a falling-out, or moral disapproval is not a valid basis for disinheritance under Islamic law.

Source: Quran 4:11-12 (fixed shares); general Sunni fiqh on the impermissibility of disinheriting a Quranic heir, and the established exception for a killer barred from inheriting the victim's estate.