So I'm bilingual, english and french. I have always understood both languages but when I was younger I would only answer in english. My poor grandmother, she would ask me something in french and would get the answer in english, I am not sure if she actually understood most of what I said to her.
We speak to Ollie in french and english, he actually seems to understand us pretty well in both. The words that he uses are mostly in english. He seems to be a bit slower on the language-speaking milestones but we have been told by many bilingual families that their kids started slower but when they get going the speak both languages, pretty well.
When I was in high school I took a spanish class, it came in useful on our trips to mexico and spain, I was able to ask for directions, find the bathroom, order food and drinks... the usual stuff when you have a really limited grasp of a language.
I have always wanted to learn other languages too, I got a dummies book for Japanese, I memorized a couple words but I would love to actually be able to visit the country and get around without too much difficulty.
Do you speak any other languages? Did you learn it out of necessity or because you wanted a challenge?