The bubonic plague was a painful disease, with black buboes, or swellings, in the groin and armpits, which lasted up to a week. There was some chance of surviving if the buboes burst.
As of 2015, full retirement age is 67 if you were born after 1960. The amount you receive doesn't change because disability benefits were calculated based on what you would receive at retirement age. However, you may see an increase if Social Security provides a cost of living increase.
If they are old or disabled enough to draw benefits, then you may qualify, depending on your own age and the length of the marriage. The minimum age for Social Security retirement is 62; you can apply for disability benefits at 18 or older. Taking Social Security retirement before your full retirement age, however, means your benefit is permanently reduced. Full retirement age varies from 65 to 67, depending on the year of your birth.