Why was aram surprised to see mourid with horse

In the story "The summer of the beautiful White Horse" Aram was surprised to see Mourad his elder cousin with the horse because their family was so poor that they could not afford a horse. Mourad and Aram belonged to family that lived in amazing poverty and hardly earned their bread and butter. Despite of the utter poverty, the family was known for their honesty and integrity. Aram was amazed to see the horse with Mourad as he knew that he would not have bought the horse.