There will be a time when your baby will be just there, but not signing yet. This will be when their “receptive” language, meaning their understanding of the words you say and their use are coupled, but their “expressive” language, their ability to communicate based on their understanding hasn’t yet caught up. Expressive language is a developmental milestone and will happen even if you don’t sign, but signing helps it along because it decouples it from the mechanics of speaking. This is all getting complicated, but the point I want to make is that there will be a time when your baby understands what you are saying or signing, but isn’t yet able to motivate their bodies to replicate the sign – to communicate.
How do you know when this happens? Well, you just look for signs of understanding, such as their eyes lighting up, bouncing with joy, or looking toward an object. For example, say you are signing MILK and what to see if you are even getting anywhere. Just do the sign and say it and watch for your baby’s eyes to travel to the milk. Try putting it on the floor with some other things. When you sign, do they look to the bottle? Before your baby signs, and for babies that are never taught to sign, this is your current reward, this is proves that your baby gets it. A baby can have a receptive language in the hundreds of words, but by comparison, their receptive language might only top 50. This is ever increasing though and eventually receptive and expressive language are nearly equal. I say this because I’m bilingual, but not exactly one hundred percent proficient. My reading and comprehension of French is much more advanced than is my ability to speak it. I have lost of lot of my expressive language even though when I listen to someone speaking French, I understand almost every word.
When we taught my son the sign for WALK – a motivating sign, done by moving the hands up and down as if they are fit hitting the ground, he would instantly get excited and run toward the baby gate. We knew that he understood what we meant – we just had to wait for him to catch up and do the sign himself.