Adobe Sign Salesforce Integration - Display child records of custom object into a document

Hi! We are on Adobe Sign version 21.5.11, was wondering if it's possible to dynamically display the data from child object records into an Adobe sign document. 

For example, I have a Cars child object which has a lookup to the Account object. My Cars object has 3 fields: Model, Manufacturer, Year, and I can have an X amount of child records. If I have 5 child records, I would like to display all 5 child records and their corresponding fields in the Adobe sign document. Is there a way to do so dynamically?  

I've already looked at the merge mapping guide but it doesn't say anything for child records of custom objects: https://helpx.adobe.com/sign/using/salesforce-data-mapping-templates.html  

Also saw this post which didnt really help much.. 

https://community.adobe.com/t5/adobe-sign/merge-mapping-line-item-salesforce-records-into-a-document-for-signature/m-p/9583654?page=1