C C had two children by an earlier marriage. What I know of this is very little. The children were named Harvey and Antonia. Here are some letters from Antonia while she was off at a music school in St. Louis. C C paid for this, and apparently Antonia lived with him and Carrie in Fulton for some years.
The Ursuline Academy of St Louis has been in operation since 1848. Today it is a private Catholic day school and the tuition for 2010-2011 is about $11,000. I do not know whether it was a boarding school in 1908 or whether Antonia lived somewhere else in St. Louis, but I suspect it had boarding students at that time.
Here is a photo of what the school looked like in 1908.
Her studies, beyond religion, were directed towards music, it seems.
At the time, "Mrs. Hofmann" was a definite 27 years old and had been married for about 4 months. They must not yet have been very good friends.