I've searched this name here:
http://www.meertens.knaw.nl/voornamen/vnb/It seems to be a relatively common name in Friesland and it derives from the male name Baue. Baue is a highly abbreviated and distorted (in a childlike manner)
German name, or possibly from the names Bavo, Bovo, Buo.
Many Frisian names have this child-distortion origin.
A similar name with apparently the same origin is Baukje