The song that Yoko is singing is a well known Japanese children's song called 'Zo San' (the Elephant), the lyrics were written by the poet Michio Mado and the tune by Dan Ikuma, the lyrics go, 'Elephant elephant, why is your nose so long? Yes, my mother's nose is this long too. Elephant elephant, who do you like most of all? I guess I like my mother most of all.'
Renée's cat is called 'Léon' in the French credits and in the dialogue, but is called 'Leo' in the English subtitles. This is because Tolstoy's Russian name of Lev is translated as 'Leo' in English and 'Léon' in French.