Using PnPJs create Collection object and save in a sharepoint list

Question

Hi,

 

I have a scenario like parent list record will have multiple child list record. I want to save all the child record ID, Title, Date field value as a JSON object in parent list column. If i create any child item then parent list json object should be updated and if i delete the child item id it should be removed from that json object. 

 

Please assist me. 

 

Thanks