Pushinka

During the Cold War, Soviet leader Nikita Khrushchev and US President John F Kennedy wrote to each other regularly. Despite the hostility between their countries, the two men also exchanged presents. One was a dog called Pushinka, whose mother was one of the first dogs to fly into space and return alive.

"My mother told a funny story," says Caroline Kennedy, who is now the US ambassador to Japan, but was once - a little over 50 years ago - a toddler growing up in the White House.

"She was sitting next to Khrushchev at a state dinner in Vienna. She ran out of things to talk about, so she asked about the dog, Strelka, that the Russians had shot into space. During the conversation, my mother asked about Strelka's puppies.

"A few months later, a puppy arrived and my father had no idea where the dog came from and couldn't believe my mother had done that."

The puppy was Strelka's daughter, Pushinka, listed on her official registration certificate as a "non-breed" or mongrel.