When do babies learn what no means?

I have a 14 month old daughter and I’m wondering when do babies start to learn the real meaning of “no”. We try to not overuse it, but sometimes there is no other thing to say when she is trying to do or get to something that is completely off limits. She can be relentless sometimes when she is determined to get to something. For example, our living room book shelf was a big no no because of the books she wanted to grab off it. She would start to rip pages out and I honestly just didn’t want to have to constantly clean up books throughout the day. For months we tried everything - saying no, moving her to something else and distracting her, patting her hand and saying no. I could tell she knew she wasn’t supposed to be doing it because she would test us by looking and reaching, shaking her head no, waiting until we looked away, ETC. it got to the point that I moved all the books into the closet. I can’t rearrange every thing in my home in order for her not to do something and I don’t want to teach her like that. But when we say no, she becomes so relentless about doing something. My question is: how much of “no” is getting through to her and how do babies that age perceive it??


She is testing her boundaries. Just keep redirecting consistently. She’ll figure it out.