Hi, commenting from Nova Scotia ...
I am researching Kleinertz in the Rhineland (my earliest records are from the late 1600s, Cologne)
I haven't come across Christine Wilhelmine (yet).
Here is what I CAN say: The Kleinertz are (arch)catholic.
The only time you'd find them in protestant church records is when they are in the military for a unit that is administered in a protestant jurisdiction (e.g. 4th Dragoon Regiment is the 1st Silesian Regiment, so there are some entries dealing with Kleinertz, but they are clearly marked as catholic).
Also, I would like to respectfully comment on Dave's find regarding Christine Kleinertz in the 1920 Address Book. That is not the person you are looking for. The "Ww" stands for Witwe, aka Widow. Christine is the widow of Wilhelm Kleinertz (who happened to be a sculptor and she is his second wife). It's very rare that a woman who is married has her own business at that time.
I will keep my eyes open, sure. She might be part of the Euskirchen lineage of Kleinertz, established in the early 1800s, but she is not documented there and none of the people in that line are documented to have resided in Bonn.
But my suggestion is to do the following:
Given that you have her birthdate, it would be easiest to contact the Landesarchiv fuer Personenstandsdaten in Duisburg. With the name, the date and possibly the locations of Bonn, Cologne, Euskirchen (in that order), it should not be too expensive to obtain the record that we are looking for.
I'd be happy to cooperate on this.
PM me if you'd like.
S.
