Create parent, children and grandchildren json file from a dataframe

I have a data frame that looks like this:

https://drive.google.com/drive/folders/1GuTgLGwM6hyIJhTaavoMpnkos9qM64xJ?usp=sharing link to dataframe

I am trying to create a JSON file in the following hierarchy: The first column should be the parent, the second column should be the children and the rest of the columns should be the grandchildren. Can someone suggest me a pythonic way of creating such a JSON file structure.