> they can leave pretty much at any time due to FMLA, and hiring someone else is not feasible (due to law). Why? Around here you see plenty of job offers that

> they can leave pretty much at any time due to FMLA, and hiring someone else is not feasible (due to law). Why? Around here you see plenty of job offers that go "must start on X and will be terminated on Y (1 year later) -- to replace an employee on maternity leave". I would imagine you would publish that offer plenty of months in advance to X, so you'll have a replacement person hired on time.