Complex sentence: Catherine in 1894, David in 1895, and Frances in 1898--prompted Wright to sacrifice his original home studio space for additional bedrooms and necessitated his design and construction of an expansive studio addition to the north of the main house.
Split into simpler sentences: Catherine in 1894, David in 1895, and Frances in 1898--prompting Wright to sacrifice his original home studio space for additional bedrooms. Thus, moving his work space necessitated his design and construction of an expansive studio addition to the north of the main house.