LFS:  The real question is "Does your wife have 40 "credits" to qualify her for SS benefits?"  If the answer is "yes" she qualifies and can receive benefits based on her earnings and SS contributions when she reaches the "benefit eligible" age.  If she is "short" of those 40 credits she will need to work in a SS eligible job for enough additional quarters to reach that threshold.
How do I earn Social Security credits and how many do I need to qualify for benefits?
We use your total yearly earnings to figure your Social Security credits. The amount needed for a credit in 2016 is $1,260. You can earn a maximum of four credits for any year. The amount needed to earn one credit increases automatically each year when average wages increase.
You must earn a certain number of credits to qualify for Social Security benefits. The number of credits you need depends on your age when you apply and the type of benefit application. No one needs more than 40 credits for any Social Security benefit.