The Advantages of Learning a Foreign Language

I always envied a lot of these people who spoke multiple languages you know like I've met some people who speak up to nine languages probably not all natively almost indefinitely. How many years it takes a child to learn a language to competency and we all think that children have this magic gift for language learning when in fact how many years does it take the average child from when they're born to when they can have a conversation with you as you would have with another adult in your native language? It would be at least 15 years maybe maybe 20 years maybe even longer than that for some people. Yet taking any of you listeners I'm sure out of your native language and exposing you to any