Congrats to your wife and my apologies for not getting to this topic sooner. I took some time off
I guess it depends on where you are heading for your MBA (if you are that is) and what her goals/plans are. If she is staying in her field and does not plan to change her industry, I think Kellogg could be a great choice with lower opportunity cost. At the same time if she does not have strong brands on the resume and wants to go into Tech, MBB, or Finance PE/IB roles, I would strongly consider Wharton.
Kellogg has its strong points too - consulting, CPG, and Tech are strong though MBB will be competitive across the board and without a summer internship could be tricky to recruit since it would be just a few months into her MBA, competing with seasoned 2-nd years unless there is a different track for the 12-month program.
FuturePM91 - do you know by chance how it would work for the 12-month MBA?