paragraph: Lighting a cigarette, he started for the lake and Grace returned thoughtfully to the house.  Mortimer hated Cartwright and Grace admitted he had some grounds.  Although her brother was indolent and philosophical, he did not forget.  Rude disputes jarred him, but if by some chance he was able to injure the other, Grace thought he would do so.  Grace, herself, strongly disapproved of Cartwright.  All the same, he was her step-father and she had tried to cultivate her sense of duty.  She was prejudiced, cold, and censorious, but she meant to be just and did not like Mortimer's bitterness.  Cartwright was occupied for some time at Montreal, and the birch leaves had fallen when he returned.  The evening was dark, and chilly mist rolled down the dale, but a big fire burned in the hall at Carrock and tall lamps threw a cheerful light on the oak paneling.  A flooded beck roared in the hollow of a ghyll across the lawn and its turmoil echoed about the hall.  Mrs. Cartwright stood by the fire, Grace moved restlessly about, and Mortimer appeared to be absorbed by the morning's news. 
question: Where was Grace's step-father occupied?
answer: Montreal