Insert node at specific index under parent node.Iindex

I am using react-sortable-tree in my application to create a funnel. I have a use case where I have a two buttons on child node to create another node under and above it. I need a method where I can pass parentKey and index so that new node is create under parent at specific index.


I did not find any function like addNodeUnderParentAtIndex which can do so.

Any help on how this can be done is appreciated!