Wontanlim3.... just because you have a SSNHL does not mean every one has the same ailment...
To the OP
First of all, I would advise you to visit an ENT that has a licensed Audiologist on staff, not a techy, not a "hearing specialist"
Tests:
Tympanometry
Pure tone audiometery air and bone
Speech play audiometry
If there is any inclination of an issue, then an OAE should be done
Still positive for an issue, then an ASSR should be done.
If they want to do an ABR.... well as an audiologist and a parent I would prefer an ASSR. ABR studies only give you about 20% of the information an ASSR can provide.
Regarding the tests for parents and cause etc.
I would imagine some genetic testing could be done.
Considering hearing loss is the Number one birth deffect, odds are, you will never really know what caused this loss.
http://www.hearingloss.org/learn/factsheets.asp
I know this is a scary road to be on, but with today's technology, your child does not have to live a limited life.
You are doing the right thing, research and learn, consult with parent of Hard of Hearing children, consult with Audiologist and ENTs.
Consult with you local govt institutions, you will be surprised to find that there is a lot of help and support out there.
Good luck
(and to add a glimmer of hope) I think your child has a conductive loss, and the person that did the testing does know what he or she is doing...... (At least I see that a lot)
Don't waste time now. Quickly give your child strong dose of oral steriods or better still, get steriods jabs into the ear, as time is crucial. Some ENT said that after certain time, chance of recovery is zero. The cause is still a mystery : may be virus, tiny blood vessel broke or a thousand other questions.