Parent/Daughter/Sister Company and Subsidiary

I know some people were confused about this during class. I hope this helps.
So, there is a parent company. Under the parent company, there can be subsidiaries. There can also be sister companies under the parent company.

Parent company:
http://en.wikipedia.org/wiki/Parent_company
http://endic.naver.com/enkrEntry.nhn?entryId=be09c7ad55df4575a86299599076d693
모(母)회사


Subsidiary:
http://en.wikipedia.org/wiki/Subsidiary
http://endic.naver.com/enkrEntry.nhn?entryId=6a76d7e0f334424988b708cd58ccc36e
1. 부수적인   2. 자(子)회사의   3. 자(子)회사


Sister company:
http://endic.naver.com/enkrEntry.nhn?entryId=be09c7ad55df4575a86299599076d693
http://endic.naver.com/enkrEntry.nhn?entryId=9ab9ec950d334a5d99e8319c199934bb
자매회사