Trainer Gai Waterhouse made headlines again Friday at Australia's Magic Millions Gold Coast yearling sale when she picked up her second consecutive session-topper. \nWaterhouse bid about $570,400 for an Encosta de Lago colt out of River Song, a Fusaichi Pegasus mare. The dam is unraced but hails from the richly productive family of Redoute's Choice, Australia's leading sire.\nCoolmore Stud consigned the yearling colt, whom Waterhouse bought on behalf of David and Luke Henderson.\nWaterhouse also sprang for Thursday's session-topper and the current sale-leader, another Encosta de Lago yearling. That one was a filly out of Ha Ha that Waterhouse bought for about $644,000 on behalf of Craig Thompson's Mount Hallowell Stud.\nAfter its third session, the auction had sold 439 horses for about $51,865,460, down four percent from last year's aggregate for 420 yearlings. The cumulative average was 5 percent lower at about $118,145. \nThe auction's first section was to end Saturday.