My mom will soon start taking her own benefit when she turns 62. When she turns 66 she will switch over to the widow benefit.
The problem is that for the next few years she will be earning over the ~$15,000 limit where they start reducing the SS payments. I understand that normally in this situation whatever amount you lose gets paid back eventually through a "recalculation" of the benefit at full retirement age.
But would the widow benefit be recalculated to account for the payments lost on her own benefit? If only her own benefit is recalculated, she will lose all that money because she won't be taking her own benefit after full retirement age.
Earnings limit and base for benefit recalculation
Please contact the SSA directly for this. This is an edge case which is not well documented.
The recalculation method is described fairly well here :
http://www.ssa.gov/retire2/whileworking3.htm#a0=0
In essence, for each month you lose Social Security benefits due to the earnings limit, your start date for recalculated benefits (when you really retire) is moved back one month. This later start date increases the final benefit.
However, I am not sure which "base" (self or widow) is used for recalculation in your case. Please contact the SSA for this.