One day, they got into an argument to prove their superiority. To decide who was better than the other, they decided on a challenge.
Each of them was supposed to fly with a bag filled with something in their beaks. The crow who could fly up higher would be declared the best.
But Sonu was a mean crow. He put cotton balls in his bag and salt in Monu's bag. Then the two crows took flight. Soon Sonu was flying higher than Monu, as he had lightweight cotton in his bag. But Monu could not gain height due to the salt in his bag.
As the crows were flying, it started to drizzle. The cotton in Sonu's bag soaked up the raindrops and grew heavy.
On the other hand, the salt in Monu's bag melted away in the rain and became very light. Now Monu flew up higher and thus won the challenge.
In spite of cheating, Sonu could not win the challenge.