How to get Children and Grandchildren included in filter results?

[Hollis Sosnowitz]

I'm trying to create the following search Parent Link in (filter=30760).

In other words, return the issues where the Parent Link is in the result of a predefined filter.

where Filter=30760 is: Issuetype = Initiative.

 Ideally I'd like the children, and grandchildren. This is to help me set up a portfolio plan.

Help?

[Hollis Sosnowitz]

I have tried using scriptrunner:

 issueFunction in issuesInEpics(""Parent Link" in (INF-1268, INF-1267, INF-1266, INF-1265, INF-1264, CO-937, SNAP-275, INF-1263, INF-1262, INF-1261, INF-1260, INF-1271, INF-1272)

That's basically asking for all issues in the epics whose parent is an initiative - though I called out each initiative. It is giving an error: 

I don't know why. Especially since it returned over 50,000 results for another search, and this is definitely less than that.

Please help!