If a relative is seriously ill or you are very worried about losing someone, dreaming of this person's death may indicate a kind of worry and anxiety.
From the perspective of western dream interpretation, Freud once pointed out that it is very sad to dream of the death of relatives and friends, which is often the reappearance of children's desire to hate relatives and hope that relatives and friends will die because of an event, but I personally think this explanation is not universal.
In addition, dreaming of the death of a loved one may also symbolize that a person's heart is becoming indifferent or depressed. Because you don't understand your reality, please judge what kind of explanation you should belong to according to your own situation.
Also, if the relatives who died in your dream are particularly dependent on you, it reflects your spiritual growth or feeling helpless.