CNN  —  Lucas Hunter loves to kitesurf, so along with his sister Sophie he planned a trip to Colombia to take advantage of the “good waves” in the north of the country in late December last year. After an illness left Sophie unable to go on the trip, Lucas traveled alone for what was supposed to be two-and-a-half-week long vacation. Sophie hasn’t seen or heard from him for more than two months, after he was detained close to the border with Venezuela. Sophie said her brother, an American