death of sisters of Sita

it is believed that all 4 sisters died as a suhagan. It is believed that after Sita bhumipravesh the 3 mothers died with Kaushalya Sumitra Kaikeyi in order of their passing. After that Ram ruled for 11,000 years the 3 sisters took nidra samadhi. After that brothers took jal samadhi. According to anand ramayan, the 3 sisters embraced the body of their husbands and left their bodies and went to heaven entering the pyre. But I want to go with 1 theory, if makers show it would be great.