VATICAN CITY — A boy stole the show at Pope Francis' Vatican audience on Wednesday (Oct 20), getting a seat at his side and a white papal cap as a reward for persistence after walking onto the stage.

The boy, who Francis later said had a medical "limitation", was wearing a mask and a track suit and appeared to be about 10-years old.

He approached the pope with tottering steps at the start of the audience in the large Paul VI hall. He caused no alarm for security officials, who did not try to stop him.

He shook the pope's hand, jumping up and down in front of him. When it became clear that he wanted to stay for a while, Monsignor Leonardo Sapienza, the head of protocol, got up and gave the boy his chair at the pope's right.

The boy, who applauded enthusiastically once seated next to the pope, walked on and off the stage freely, returning to the centre several times as the audience continued with the pope reading his address.

The boy several times pointed to the pope's white skull cap, known as a zucchetto. Officials took the hint and he was given a similar cap, prompting applause and laughter from the crowd of several thousand people.

"I thank this boy for the lesson he has given all of us. May the Lord help him in his limitation, as he grows, because what he did came from the heart," the pope said. REUTERS