She gives a greeting to the baby

I'm again watching this interesting video, but I'm not sure what is (At 0.38) "gives a greeting", since the mother doesn't really say "Hi" to her baby.

Hence I'm wondering if "to give a greet" means maybe to make a gesture toward the baby?

In this "still face" experiment, what the mother did was she sits down and she's playing with her baby who is about a year of age… "Are you my good girl? Oh, yes…"

And she gives a greeting to the baby, the baby gives a greeting back to her: "Dah!". This baby starts pointing at different places in the world.