well... not exactly.
French people don't go home and speak English at night, contrary to the beliefs of many. In the same way, a someone who's first language is french doesn't translate French into English, then understand it. They see "Oui maman! Je suis grand maintenant" as just that.
Translations simply help people who don't understand the language. French doesn't translate well into English because it's a different language. That's the thing about translations, and about languages in general. They weren't designed with the intent to translate. That's why there's so many words that have no direct translation to English. Hence, in English it's boring, but in French it makes as much sense as "Mommy, wow!..."
This is also the most interesting thing about learning a new language - at a certain point in your process, you stop having to translate and simply start understanding it as French, as opposed to "an English word in French."