Languages are but different manifestations of one bigger entity called The Language. I daresay I understand something about the nature of this organic and dynamic phenomenon.
I am native bilingual. My mother tongue is a dialect very close to modern Turkish, which I also master as any native speaker since I live in Turkey for years now. My second native language is Russian, the language of my formation so to say, the one I feel most confident with. If there would be a notion of "native trilingual" I would add Romanian as my third native without hesitation, although it is not my native properly speaking. Born and grown up in Moldova, where Romanian is the official language, and spent 5 years in Romania and graduated University there, I was always in contact with this language and I can't recall making a special effort to learn it. It came naturaly, the way one learn his/her native language.
English is my first 'second language aquisition' where efforts have been made to understand the grammer and memorize words.
Laguages and the science of linguistics are considered the most boring thing by many, not for me - I view it as a hobby. I grasp new languages with an easeness which make some people envious and some frankly admire.