Lookup and List.Distinct, List.Sort within same table

[FruitBat]

In my content management system, I can make a relationship between table rows (and their respective IDs).

The original or "base" table is Table 1, and it contains all rows.

I've replicated that table and renamed it Table 2.  Table 2 has distinct "Child_IDs" from Table 1.

The two tables - Table 1, and Table 2 - are then related using a one-to-many relationship on "ID" (Table 1) and "Child_ID" (Table 2).  See the attached PBIX.

Here's Table 1.

ID	POSTED_DATE	DOC_NO	TRANS_NO	VENDOR_NO	FISCAL_YR
1	20210518	N45067112	199	VN00001233	2019
1	20210518	N45067112	199	VN00001233	2020
2	20210518	JV43667225	300		2021
3	20210518	R538024467	400		2007
4	20210518		500	VN00012544	2017
5	20210518		600	VN00015749	2021

And Table 2.

ID	Child_ID
1	2
1	3
4	1
4	4
4	5

The result I need is a table of columns that distinctly list, in ascending fashion, related dimensions from other IDs.  Generally, I prefer to do this in M Query, but I suspect it can be optimized in DAX, as well.

For example...

ID	POSTED_DATE	DOC_NO	TRANS_NO	VENDOR_NO	FISCAL_YR	FISCAL_YR_CHILD
1	20210518	N45067112	199	VN00001233	2019, 2020	2007, 2021

Any ideas?

[Vijay_A_Verma]

1. PBIX file is not attached.

2. I have a follow up question. Will it have a cascading impact through relationship. For example, 4 is related to 1 which is in turn related to 2 & 3. Hence, will the output of 4 contain elements from 2 & 3 as well. 

[FruitBat]

Hello, Vijay.  Great questions. 

No - there's no expectation for cascading relationships (or any expectatation that they be queried, for that matter).

Apologies - seems I can't upload the sample PBIX.  

For context, I've tried to merge and append tables to create a unified solution, but without much luck; and I've attempted a few LOOKUPs and SELECTEDVALUE measures, but no luck there, either.  Nor with CONTAINS, but I believe that only returns True(), rather than values (?).