Mother Mary and the extra key

Padre Pio used to tell a story: "One day Our Lord making rounds of Paradise saw some strange faces. He asked Peter: 'Who let these people in?' Peter: 'There is nothing I can do.' The Lord: 'But you have the key.' Peter: 'There is nothing I can do, and you can't do either.' The Lord: 'What do you mean?' 'It's your mother. She has another key. She let's them in.'