I think the closest (English) phonetic spelling would be NEE-shə. The "s" is more part of the first syllable than the second, though (As a
Dutch person, I see the name divided into the syllables Nies and je, -je being a diminutive suffix)
See also
http://www.behindthename.com/name/niesje/submittedhttp://www.meertens.knaw.nl/nvb/naam/is/niesje (in
Dutch, but I can translate if you want)
Perhaps one did not want to be loved so much as to be understood -
George Orwell, 1984