I haven't heard of any studies specifically about emotional stress and incontinence, but it would certainly be interesting to know if others experience the same problem.
In addition to looking at how the emotional stress plays a role, you might also want to look at how physical factors could be at play during the holidays. For example, many people drink more alcohol during the holidays - a major bladder irritant. Also, different sleeping patterns (later nights, less sleep, more sleep, etc) could be a culprit. Eating different types of food might also be a problem.
Stay Dry,
Jasmine