When Max and Zoë were 1 year and 9 months old, we started playing a bilingual game with them. For example, I would ask them: “Когда мама говорит “кошка”, как папа говорит?“ (Rus. “When Mommy says “cat”, what does Daddy say?”). Max got the idea straight away. He just loved the game! He would ask me “more!” if I stopped playing the game. One could also see that he was really proud of himself when he could give the equivalents in the two languages. Zoë caught up with Max a few weeks later when she as well got the idea of the game. Fun games greatly stimulate bilingual development.