Adam resides in a beautiful home on a large parcel of property adjoining a lake. To accommodate his frequent guests, Adam decides to build a sizeable one-bedroom guesthouse southeast of his home. In 2017, Harper, Adam's neighbor, confronts Adam about the location of the guesthouse on her property. The statute for adverse possession in the jurisdiction is 10 years.

Which of the following facts, if true, would be most helpful to Harper if she attempts to quiet title Adam's adverse possession claim to the property?