Claim: Svetlana Alliluyeva was the only child of Soviet leader Joseph Stalin and his only wife Nadezhda Alliluyeva, then in 1978, she visited the United States for two weeks then return to Russia afterward.
Evidence: In 1978, Alliluyeva became a US citizen, and in 1982, she moved with her daughter to Cambridge in England, where they shared an apartment near the Cambridge University Botanic Garden. In 1967, she caused an international furor when she defected to, and in 1978 became a naturalized citizen of, the United States.