Are you a hearing parent of a deaf child? Most likely a doctor is one of the first "professionals" to consult. Next thing you may be referred to a specialist ranging from an audiologist to another medical professional.
What they will most likely recommend is a cochlear implant and speech therapy. It sounds like a reasonable solution. But, but, but. You have no idea.
What they won't likely tell you are some critical things you must know. And, the deaf child must have the rights to a fair, fully-informed decision that a parent makes at the child's earliest time of life.
After reading this, do your own further research. Further resources are provided at the end of this post.
But, it's sensitive to language acquisition.
Neuroscience studies (Petitto) show that ASL speaking/listening activates the same linguistic regions of the left brain as English speaking/listening! What does it mean? The brain is amodal -- that is, the brain sees no difference between the lips and the hands. It only sees language.
Linguistic studies also show similar language milestones, phonological acquisition, and language development in signing and speaking children from birth. Both groups make same kinds of errors. For example, pronoun reversal errors at around 18 months in ASL and English respectively.
Signed languages have all linguistic features in linguistics as found in spoken languages -- phonology (the smallest units of language), morphology (how words are formed), syntax, and so on.
These three things -- the linguistic regions of the brain, the similar language developmental milestones, and the existence of signlan linguistics -- are an overwhelming evidence that speech is not central to language. Signed and spoken languages are perfectly normal and equal.
I love repeatedly quoting Dr Petitto's statement: "The human brain does not discriminate between the hands and the tongue. People discriminate, but not our biological human brain." -- Dr. Laura-Ann Petitto (Gallaudet Today, Spring 2012, p. 17)
Fear not. A study shows no evidence of sign language's interference with speech development. Remember speech is not a language. English is; speech is a modality. Signing is a modality; ASL is a language.
One shouldn't be concerned about the signing's interference with speech development, because it's untrue. But, one should be concerned about speech's interference with the language development; in that unfortunate case, it is true. See many hapless deaf children with literacy and language delays.
Deaf children read and write English as another language as fluently as hearing children, given that they acquire a language (ASL) from birth and go through the language acquistion milestones from manual babbling to first word and two-word utterances to full-fledged language. In parallel, they also learn English through fingerspelling and reading.
A first language supports a second language. And two language enhance each other. Bilingualism is beautiful and highly beneficial.
In the professional hearing and medical fields, sign language is often treated as a substitute of speech, a support to speech, a secondary method, and such. It's a dangerous mindset. Be mindful of this.
Deaf baby must have an access to language with its normal eyesight and acquire a language (Ameslan/ASL) first before or in parallel she can acquire a second language (English, especially written).
Why training a deaf child's speech (modality) to accomplish producing a perfect word at age three and missing the first crucial two years window of language acquisition?
There are many cases where bilingual hearing and deaf children of Deaf parents (codas and dodas respectfully) have advanced reading levels as well as some advanced writing skills beyond their grade levels at school, even if Deaf parents with English fluency in writing don't vocally speak English at all.
After all, the majority of hearing people start learning a signed language at age 20 and onward, sometimes in teenage years. Concerned? They already have the first language (English) before learning ASL. It's more important that deaf children acquire the first language (ASL) before acquiring English in another modality (e.g. written and sometimes spoken).
Language first, regardless of the modality. Remember language is amodal.
Here is a few quotes from the book "Journey into the Deaf World" discussing results:
"There is not a single published case, after a decade of experimentation with the multichannel implant and more than a thousand implanted children, of a child acquiring oral language with an implant." (Lane, pp 395)
"...those children who could recognize at least some words has lost their hearing on the average when they were five years four months old, whereas those who could not recognize words at all using the device had lost their hearing on the average at age one year six months."
Born deaf will be always deaf to some degree.
"...the vast majority of implant candidates, eighty-six percent of whom are born Deaf, but also a small minority, seven percent of implant candidates, who lost hearing during the first three years of life and may have acquired a little or a lot of English beforehand."
What the chart above shows is that the majority of deaf babies and toddlers enter auditory-vocal therapy. Over many years, many parents feel at loss and send their children to schools that use American Sign Language. But, some of these children may experience language delay. They may struggle with a second language (e.g. English) because of the lack of language acquisition of the first language (ASL).
Research and read, get yourself educated, talk with non-phonocentric professionals for their invaluable perspectives, meet deaf children and Deaf bilingual adults from all walks of life (from mechanics to PhDs).
Inspect and challenge ideology, phonocentrism, ignorance, and audism. Remember that hearing loss is nothing more than a change of language and modality. It doesn't lose intelligence, language, communication, nor literacy. It doesn't lose anything. Just the society needs to lose its compulsive-obsessive phonocentrism and ignorance.
Bilingualism and biculturalism is all round option for every deaf child -- fluency in both languages regardless of their speech skills. It's a right for every deaf child to language, rather than priviliging deaf children with moderate speech skills while marginalizing the rest of other deaf children. There are many cases where Deaf children with a zero speech skill have higher academics than other children with good speech skills. Education matters.
Harlane Lane, et al. "Bilingual and Bicultural Education for Deaf Children." A Journey into the Deaf-World. California: DawnSignPress. 1996.
Harlane Lane, et al. "The Hearing Agenda II: Eradicating the Deaf-World." A Journey into the Deaf-World. California: DawnSignPress. 1996. Pp 379-407.
Snoddon, Kristin. "American Sign Language and Early Literacy: Research as Praxis." https://tspace.library.utoronto.ca/bitstream/1807/19092/1/Snoddon_Kristin_200911_PhD_thesis.pdf