My grandmother passed away yesterday and we are preparing the obituary. Grandma was very Dutch and used to say something to us when we went to bed. What I need is the proper spelling:
It’s welterusten without the spaces. And to expand on The Librarian’s answer: while goedenacht is another good translation of good night, welterusten is used exclusively when one of the parties is going to sleep. Goedenacht is better suited for waking situations.
As another native Dutch speaker I’ve only encountered welterusten or slaap lekker and perhaps an occasional goedenacht on more formal situations. Ofcourse, it’s certainly possible that your experience has been different. This does not seem the place to start a discussion about it. Perhaps I shouldn’t have made the first comment.