I suspect my co-worker is abusing FMLA. What can be done?

She is in her early 20's, doesn't smoke, and isn't overweight, yet she claims to have chronic constipation that only seems to surface, more than 90% of the time, on days that extend the weekend.

It's absolutely FMLA. She exhausted all paid time off and began taking unpaid time off most weeks until our boss gave her a final warning, at which point she applied for FMLA. They suspect her too but it doesn't seem like anyone can do anything, unless someone were to get a timestamped photo of her out and about while she should be at work.

5 hours ago

It's intermittent FMLA.