In real life, such a switch occurs rarely.[1]Since many cases of babies switched at birth are likely undocumented or unknown, the following is presumably not an exhaustive list.
In 1913, a baby subsequently named Jim Collins was born to Sam and Ida Benson and a baby subsequently named Phillip Benson was born to John Josef Collins and his wife. They were switched at Fordham Hospital in New York City in the early days of hospital births.[5]
In 1931, at the Leiden University Medical Center, female babies Agnes van Vegten and Lenie van Duyn were switched. Suspicions did not rise until two decades later, when the girls met at a wedding and wondered at their mutual likeness to each other's family.[6]
In 1942, at Bureå hospital in northern Sweden, two boys were accidentally switched, and then switched back after a legal process in 1945 (the case is known as Bureåfallet in Swedish). This is described in the novel Kapten Nemos bibliotek (1991) by Per Olov Enquist, who was a cousin of one of the boys.
In 1951, at a hospital in Prairie du Chien, Wisconsin, the babies of Mary Miller and Kay McDonald were accidentally switched. Mary Miller immediately suspected that a switch had occurred, as the baby she received weighed a full two pounds less than at the hospital. Mary Miller knew Kay McDonald, and assumed that it was their baby she had taken home. However, a series of circumstances kept Mary Miller from actively pursuing her suspicion for 43 years, when she revealed to the now grown girls, Sue McDonald and Martha Miller, what she suspected of their births. Genetic tests later confirmed that a switch did in fact occur. The story was featured on an episode of the radio show This American Life.