Well this is not actually a story, but one of the quotes from Mother Teresa which you can use in your debriefing to emphasize the power of teamwork.
“I can do things you cannot, you can do things I cannot; together we can do great things.”
― Mother Teresa
If you wish, and depending on the situation and time, you can share with the participants a little more about Mother Teresa.
I have extracted the two paragraphs below from Wikipedia for your easy reference.
Agnes Gonxha Bojaxhiu (26 August 1910 – 5 September 1997), more commonly known as Mother Teresa, was a Roman Catholic nun of Albanian ethnicity and Indian citizenship, who founded the Missionaries of Charity in Calcutta, India, in 1950. For over 45 years, she ministered to the poor, sick, orphaned, and dying, while guiding the Missionaries of Charity’s expansion, first throughout India and then in other countries. Following her death, she was beatified by Pope John Paul II and given the title “Blessed Teresa of Calcutta”.
Mother Teresa’s Missionaries of Charity at the time of her death had 610 missions in 123 countries including hospices and homes for people with HIV/AIDS, leprosy and tuberculosis, soup kitchens, children’s and family counselling programmes, orphanages and schools. She received numerous awards including the Nobel Peace Prize in 1979, and the Bharat Ratna in 1980.