Complex sentence: When she proceeded with her plans to marry Stroebele, it is believed her father immediately disinherited her and their son, Friedrich became the sole heir upon the death of his father in July 1887.
Split into simpler sentences: When she proceeded with her plans to marry Stroebele, it is believed her father immediately disinherited her. Their son, Friedrich became the sole heir upon the death of his father in July 1887.