Where was the bedroom the girls were in and how close was it to the parent's bedroom?
These bedrooms are large, high ceilinged, and virtually cavernous by the standards of us bungalow dwelling peons, but the large 6600-foot Smart home is vaguely cross-shaped (cruciform) or X-shaped, and each of the 4 wings contains bedrooms upstairs, that shared by the girls being the largest and having a wing to itself. Another wing has the master suite, and the other 2 wings each have 2 bedrooms, so there are 4 rooms in those, for the 4 boys.
Somewhere in the house is said to be a 7th bdrm, but I am assuming it is downstairs for guests with its own bath (just an informed guess).