Age of L2 Learners

I find it interesting that there really is no age limit on when someone is able to learn a second language.  Being a second language learner myself, I would definitely consider myself lucky for starting at such an early age because I was given more of an opportunity to further my growth and knowledge in the English language.  However, that does not mean that someone who is older has a disadvantage.  Again using my parents as an example, they both moved to the United States from Korea when they were in their early/mid twenties, which to some would be too late to learn English.  However, my dad's English is far better than some of the younger people that I know who have been here for at least ten years.  While I do not believe that practice makes perfect, I do believe that practice makes better.  Because he is a small business owner and constantly in contact with people every day, he is constantly expanding his social skills as well as expanding his knowledge of the English language.  Although he will call me every now and then and ask what a specific word or idiom means, he is learning just as much as a child would.