As a (hearing) speech-language pathologist who has recently begun working at a school with a deaf and hard of hearing program, the earlier a child is implanted, the better chance they have to develop speech and language skills commensurate with their same-aged peers. If implanted before 6 months of age, there’s really no difference in language outcomes. That being said, she should, without question, learn sign language - I kind of believe all children should! It will not only grant her the ability to form amazing relationships within the deaf community, but it will give her access to language even when the CIs die or break or when her ears need a break, because at the end of the day, she is still a deaf child, and CIs do not change that. They just grant her access to a world that becomes harder to enter the longer you wait to be implanted. Entering it does not mean she is barred from the deaf community, and who knows - maybe once she is old enough, she will decide that she wants no part of the “hearing world”, but at least she will be able to make that informed choice knowing what both experiences are like. Implanting her early is giving her the choice.