Child record data contained in repeatable sections will be exported to their own individual files or sheets (Excel Format). Inside each child file exports, there will be columns that will contain the parent’s record ID (one level above the child record) and also the root level record ID.
For Example: If you have an app that has nested repeatable sections, it will be formatted like this:
Root Level Parent Record -> Child Repeatable section -> Child level 2 Repeatable Section -> Child level 3 Repeatable Section.
The file that contains the child level 3 repeatable data will contain both the ID’s for the child level 2 repeatable section and the root level parent record.