When Lord Rama reached the ocean to go to Lanka, he needed a bridge to cross it. The monkeys were helping him construct the bridge. They were carrying heavy stones on their backs.
A few monkeys were carrying large stones, while some others were able to carry only small ones. Lord Rama was supervising the work being done by the monkeys.
A squirrel had been watching the monkeys doing construction work. It was also inspired to see the monkeys helping God. It too wanted to offer some help, but he did not know what to do.
Suddenly, the squirrel got an idea. It rolled on the sand and then washed the sand in the water of the ocean.
As it got wet in the water and came back to the sea shore, it got more sand stuck to its body. Thus the squirrel was happy to have participated in the construction work and do whatever little it could.
Lord Rama saw the innocent act of the squirrel and watched for some time. He knew the squirrel was trying to help him with whatever capability it had.
He called it and said, “You are too little but your deed is too great. I am extremely pleased with you.”
Lord Rama put his hand on the back of the squirrel to bless it. The three lines we see on the backs of squirrles, symbolise the finger marks of Lord Rama.
Moral : Do whatever you can for a good cause.