According to the marriage record of Dorpat/Johannis on 2.4.1827 Charlotte’s father Johann Reimers was manager of a manor,
Gutsdisponent.
It seems that Charlotte was not born in Dorpat, as she does not appear in the birth records of the german congregation, either in Dorpat/Johannis or in Dorpat/Marien. According to
Erik Amburger: Die Pastoren der evangelischen Kirche Russlands, 1998, page 259, Charlotte was born
bei Dorpat, i.e. in the region, not in Dorpat proper.
The confirmation day 17.6.1823 of Charlotte Dorothea Reimers can be found in the communion-book of Dorpat/Johannis. There she is daughter of the late manager,
des verst. Disponenten Johann Reimers and his wife Anna, geb. Gallatz:
Saaga EAA.1253.3.4:534.
Later, on March 25th 1825 a manager’s widow,
Disponentenwitwe Anna Reimers with
Mademoiselle Charlotte Dorothea Reimers (and her future husband Carl Behse) appear in the same book:
Saaga EAA.1253.3.4:364
Apparently Johann Reimers had been working on some manor outside Dorpat. My guess is that his wife Anna and daughter Charlotte had moved to Dorpat after his death.