What am I missing in this sentence?

[mewes6190]

皆さん、こんにちは。

At first, let me reintroduce myself. I studied pretty hard and was quit active on these forums a couple of years ago, before I had to take a pretty long hiatus.
Anyway, now I'm back at studying and trying to get a firm grip on an N4~N3 Level. For that, I'm trying to daily read one or two articles on the News Web Easy Website.
So, yesterday I tried this article:
http://www3.nhk.or.jp/news/easy/k10010923011000/k10010923011000.html

and while I pretty much understood the whole article, I can't get the exact meaning of the last sentence, because I can't exactly get the meaning of the quote. Maybe somebody can help?
The whole sentence is: "お母さんは「息子が生きていた証明をもらうことができました」と言いました。"

Now, the quote gives me headaches, 'cause somehow it seems to be missing something. 息子が生きていた証明をもらうことができました to me translates roughly as "When my son had been alive, certificate could have received", but that doesn't make sense. Does his mother WISH, he COULD have received the certificate while still alive (which would make sense to me)? And if so, where would I get the "wishing"-part from?

I'm glad for any help or suggestion.

また、
くろくま

[thegooseking]

くろくまさん、お久しぶりですね。

I don't really get it myself, but I'm leaning towards reading it as "I was able to get proof that my son had been alive". Not proof in the sense that there was ever any doubt or anything, but, reading between the lines, in the sense that she's comforted to have a tangible memento of it. Like, she's glad that there is evidence of what he did in his life.

That makes sense to me, though I don't know whether it's what was actually meant.

小狼

[mewes6190]

小狼さん、はい、そうですね。おはよう。

Actually, that's one interpretation I also had in mind for a second, but I couldn't fit it in the broader context of the article.
Maybe I'm preoccupied, because 証明 appears in the article before in the meaning of a certificate, and I'm desperately trying to get an understanding, where this 証明 refers to the same object as the 証明 before. Of course you could be right that it's a totally different 証明 with a different meaning.

At least your interpretation would make sense.

Best
くろくま

[community.japanese]

くろくまさん, 小狼さん、
こんにちは。
I think 小狼さん’s translation is good.
証明 has several meanings, proof, testimony, demonstration, and so on.
Here it means proof.
Yuki 由紀
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