Sergeant Preston of the Yukon [Quaker Cereals giveaway] #[1]

Six years before the gold strike, six-year old American-born Bill Preston and his parents steam upriver to the Yukon where his father sets out to make a living as a trapper. At seventeen, Bill goes to college in America, but at graduation a telegram informs him his father was murdered and the killer got away. He joins the Mounties believing he will one day corner the killer. After he passes the training and becomes a constable, the Inspector partners him with Corporal Ryan. He proves his worth apprehending a thief. Ryan says he will tell the Inspector that Preston needs no nursemaid.