Meaning of sentence ending もん


> 「でも時々いるわよ。私のクラスでも犬に追いかけられたって話、たまにきく **もん** 」  
>  父ヒロシに続いて、お姉ちゃんが冷静に言った。  
>  "You occasionally hear stories of being chased by stray dogs even in my
> class" said her sister calmly, following on from dad.

My understanding of もん comes from [this
answer](https://japanese.stackexchange.com/a/69174/7944), which suggests that
the ending makes the sentence somewhat emphatic. But this doesn't seem
consistent with the sister speaking calmly (冷静に).

Does もん have another meaning? What am I misunderstanding?




It's within the "emphatic" use of もん in my opinion. 冷静に might be better
translated as "coolly" in this case. 冷静に suggests the person in focus (お姉ちゃん
in this case) is being/looking cool-headed while someone else is overly
excited. In other words, I would imagine she is not too loud but sounds
confident.




It is the same もん. To me, the particular case sounds like adding nuance of
_for/because_ : _There are such cases, for I hear some class mates..._

It is a usage of the following definition (ア):

> [もの](https://dictionary.goo.ne.jp/word/%E3%82%82%E3%81%AE/#jn-219750)［終助］ １
> 活用語の終止形に付く。多く「だって」「でも」と呼応して用いる。現代では多く女性や子供の間で使われるが、時に撥音化して「もん」となることもある。
>
> ㋐不平・不満・恨みの意を込めながら、相手の自分に対する非難に対し、根拠や理由を示し、反駁 (はんばく)
> 、訴え、甘えなどの気持ちを表す。「だって時間がないんです―」「でもお父さんがそうおっしゃったんです―」
>
> ㋑（「ものね」「ものな」などの形で）詠嘆の意をこめて理由を表す。「でもあなたと私とでは考え方も違います―ね」「なるほど、それは彼のお得意だ―な」

