Your eligibility for these benefits works on the same credit system as for retirement payouts, but there are slightly different rules about who is eligible. Eligibility for disability benefits depends on how old you are when you become disabled, as well as the nature of your disability. You can't qualify for disability benefits if you are able to work and earn more than $1,130 a month (in 2016). Your disability also must be considered severe enough to affect your everyday work-related activities. Check out the online version of the process the Social Security Administration (SSA) uses to decide whether or not you qualify as disabled.
Disability benefit payments start only after you have been disabled for five months, and they continue until your condition has improved enough that you can start working again. To estimate your disability payments, check out the online benefits calculator offered by the SSA.
If your adult child is disabled before the age of 22, he or she can qualify for benefits based on your earnings record. Anyone who becomes disabled after turning 22 needs to pass the recent work test, a measure of how many years of work you have performed depending on your age. Details of the test are available here.
If you are still receiving disability insurance by the time you reach full retirement age, your payments switch over to retirement benefits. The amount of your payments remains the same.