At any point beyond Sequence 6, return to the Davenport Homestead and, from the front door, walk around the right side of the manor and hide around the corner at the back. Whistle, and a turkey will appear nearby. Approach it and press up, up, down, down, left, right, left, right, B, A to feed it. This will result in the turkey donning an Assassin's hood and following Connor around.