I enjoy watching foreign movies with subtitles, and then trying to learn a few words in the language that way. I watched a French movie a few days ago that way, and was surprised at how many French words I already knew. I've been told that's how the Dutch learn English. The country isn't big enough to make it worth dubbing the shows, so they are shown in English with Dutch subtitles.
I never did find out how many he spoke but I wouldn't have been surprised if it was 3 (both parents from different countries in NL, they spoke English between them).