if yuo learn a language earlier one of theories is that you dont have many other cognitive abilities in your brain and so therefore its easier to pick up language The older you get the, the more cognitive abilities you have in your brain and therefore you find it harder to learn other languages It because asy ou get older you learn new things - ir in this case language - as whole chunks and cant break it down in to smaller usable chunks that can be adapted to different circumstances occasions etc.
You will find that your children may struggle to be as fluent at 2 language as other children at the same age in one language. If you want to teach your child and bring them up as bilingual, you would HAVE to fully immerse them in that language. EG, i speak french fluently and phil english, i would have to speak no other language BUT french to them ever for it to be beneficial. Evelina for eample would HAVE to speak swedish all the time, Demba speak wollof (sic) all the time and noa would learn english from everywhere else, otherwise it wont happen properly.
Evie your kids wont grow up confused.........worry not. However learning 2/3 languages (even to the point of bi/tri lingualism) as a child does't mean you;re predisposed to learn lots more language fluently throughout the entirety of your life. After a certain point generally found to be through puberty you will slowly become worse and worse and picking up new languages. Doesn't mean you'll be smarter in general if you get me!??!
Much love
x