Hi,

This "je" (you) sounds like a creche "improvement" to me. It's like singing "For YOU'RE a Jolly Good Fellow." (The songs are somewhat similar, BTW.) However, checking a bit further, it turns out that "Lang zult gij leven" (same meaning but in older Dutch) existed already in a 19th century music book.

"Zij/ze" inidcates a female person, or multiple persons. When stressed, it's always written and pronounced "zij"; when not stressed, it's in most cases pronounced "ze", regardless of which spelling is used.

"Hij" inidcates a male person. When stressed, it's always pronounced "hij"; when not stressed, t's in most cases pronounced "ie", though rarely spelt that way. Because there's no leading consonant, pronounciation will often require an initial "d", "die", to keep it separate from a preceding word, though this is not normally spelt. Whether the "d" remains from an older form or stems from the pronounciation itself is unclear.

So, "ze" and "die" is indeed what is sung, if nobody interferes with it. And, yes, "Lang zullen ze leven", where "ze" is plural, is also sung, mainly at weddings, though I expect the occasional twin will hear it as well.

I don't think we have an origin. It should be noted that earlier it seems to have repeated the first three lines, like the Swedish version apparently does. That doesn't tell us for sure which way the song travelled, though.

Bye
                                                                                                                                 Mysha