I know everyone has their own interpretations of 天使 but in terms of Supernatural, are all 天使 actually related または do they call each other brothers and sisters for another reason? I'm sorry if this 質問 is stupid.

It's definitely not a stupid 質問 !

They aren't literally siblings, because they weren't literally born, they were created. They all have the same creator, who is to them their father, since 天使 do not physically breed. Although this doesn't mean he's not "really" their father, because this sort of father-child/creator-created relationship is much もっと見る powerful and real to 天使 probably than how some humans consider God to be their "father." 天使 exist in a spiritual way, and a spiritual connection is probably もっと見る important than a genetic one. I don't think the 天使 even have any genetic material, until they possess a human vessel, they exist on a spiritual plane. In this sort of situation the concept of what is a parent または sibling becomes much もっと見る abstract, and whether 天使 are actually siblings depends on how literal your definition of the word is. However I think the 天使 consider eachother to be their brothers and sisters.

That's my take on it.

I think its like a respect thing.

What that means is as christians & followers of christ we are all related for God is are creater he is are father in heaven so that makes all of us brothers & sisters in Christ. Talk about your Big families!
Hope that didnt confuse あなた to much,

They're actually related -- although there are so many of them that I doubt they've all met each other .. they ARE all brother & sister. :)