Welcome to HealingWell!
Kudos to you for branching out and doing research for your mother. I wish my family had been as helpful.
Anyway, first and foremost, YES stress can definitely exacerbate IBS symptoms. It is quite common for most people under stress to suffer with GI issues.
What are your mother’s main complaints – diarrhea, cramping, gas, etc.? Did her doc prescribe any meds? Has he been scoped?
Sorry for so many questions, it just helps us help you with ideas.