[Closed] Family holiday with young kids - recommendations in Tuscany or nearby?

My sister is getting married in Tuscany in mid-September, so the approximate destination of this years family holiday has pretty much been set. Before we turn up at the wedding, my wife & I are planning 7-10days for ourselves and the kids (4yr & 1yr).

So, any recommendations for good family destinations/resorts in Tuscany, or within a few hours drive in any direction? After a fairly stressful year with the 1yr old, relaxtion is a high-priority, a little sightseeing or beach time would be great. We'll fly into Rome, Pisa or Florence and rent a car, but will probably try to stay put in one place for most of the time.

Thanks!