Regardless of a baby exposed to sign language or not, babies begin to point to things at about 9 months. This pointing is gestural, not the same process in the brain as pronouns (e.g. linguistic pointing for pronouns) in sign language.
Pointing is not just pointing to refer to something. It is significant because it creates a triangle between you, the baby, and the object.
For example, when a baby holds an object, like a rattle, you talk about it to her/him without pointing. The baby would only focus on the rattle he's holding or focus on you. She/he doesn't create a triangle that involves you, him/her, and the rattle.
By the time, the baby can point, she/he can draw you into what she/he is interested in. It creates a triangle.
Pointing is prevalent across ages. A range of the purpose of pointing is from localization (to specify a direction, distance, and location) to early language development (to specify an object to be named).
At late 0;8, Juli initially handpointed with the whole hand and then, with quick transition, began to finger-point toward certain locations in space where she wanted to go.
Juli was able to direct me or a caretaker where she wanted to go by handpointing toward a specific location, especially a work of art or a photograph on the wall. She handpointed and vocalized at the same time.
In addition to handpointing, Grandma Z described how she followed Juli's direction by observing the baby's body leaning toward a destination. So much freedom for Juli now that not only she could crawl, but also she could handpoint where she wanted to go!
Just in a few days from the emergence of hand-pointing, I noticed Juli began to form an index-finger pointing toward things in the space.
Juli had been pointing at things in the environment for the past weeks. Initially, she pointed to direct me where she wanted to go.
Then something was different. Juli pointed at things for a different reason. It was more about communicating what she saw or thought. With that, I found myself naming things she pointed at.
From there, with the power of finger pointing as a form of communication, pointing no longer functioned solely as a direction. Juli grew more interested in pointing at things and listening for their names.
This naming stage had just begun to emerge.
A month before, Juli (0;8) first formed an index finger and pointed to direct where she wanted to go. Then she discovered that she could point at things in the environment for names.
Then I noticed the other week that Juli (0;9,2) began to point at the pictures in a book for names. It gave me a new window into her mind what she was seeing!
Whenever Juli pointed to an image in the book, I articualted an ASL word referring to what Juli pointed at.
Another thing was that Juli turned the page one by one by herself. It gave me an insight into how long Juli preferred to "read" each page. I helped separate the hardboard page using my fingernail, but she lifted and turned the page herself.
In the scene in the video where the book was upside down, I suggested Juli to turn the book around and helped her turn it around. In the right format, Juli tapped on her lap and finger-pointed to the image of the dog.
But, she also referred that expression to other furry animals. Eventually, she learned to categorize the furry animals later.