We should consider the fact that not everyone was brought up with the same manner and custom.

英訳に間違いが有れば正してください。

我々は誰もが同じ風俗習慣で育ったわけではないという現実を考慮すべきだ。
We should consider the fact that not everyone was brought up with the same manner and custom.

ヒント
風俗習慣

答え
manner and customを manners and customsにする

We should consider the fact that not everyone was brought up with the same manners and customs.

行儀、風習の意味でmannerは複数形