I think Cooper is popular with kids that can drink….. a day with Sherwin in Anegada would trump Cooper and snorkeling the Rhône for my crew. We are divers - did the Rhône. It was fine to do as a dive (once) to say we did it. I don’t know how much you can really take in snorkeling. We don’t visit the BVI for snorkeling and diving (although we do a little of both while there). Sharkplaneo and the Dogs would probably be more fun for the kids if you have a calm day and good viz. I would head to North Sound from Norman - long day but doable. Then do Baths via taxi from there, head to Anegada and then JVD.