Make the baby sign for key by taking your dominant hand and hooking your index finger. Use the knuckle of that finger and twist it against the palm of your other hand, like turning a key in a lock.
Keys are probably objects your child is always curious about or wants to play with. Teach key by showing your baby the keys, signing for it, and opening a door.
Babies love key chains and keys. As a word of warning, keep in mind that many keys have been lost as a result of curious babies playing with your key set.
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