you are likely to find Football in/at/on Roof. Roof is part of Truck. you are likely to find Horn in/at/on Truck. Horn is related to Vehicle. 
Mark is related to Boy. Boy is related to Baby. Baby is related to Cattle. 
Football --AtLocation--> Roof --PartOf--> Truck <--AtLocation-- Horn <--RelatedTo--> Vehicle 
Mark <--RelatedTo--> Boy <--RelatedTo--> Baby <--RelatedTo--> Cattle 