I'm not sure, but maybe her mother was named Verhage. Members of the Wieland family are still living in Indonesia and you van find a "familie Wieland" site on Facebook. Gerrit Wieland was until 1906 a soldier in the KNIL (Royal Dutch Indian Army) and got a medal (Militaire Willems Orde)in 1901. He married in 1898 and died at the age of 73 in Makassar in 1941. His widow died in 1954 also in Indonesia.