My kids are 4 and 6, is this appropriate for their age?
Yes very safe and fun!!
They could certainly enjoy watching the sharks, rays and other marine life from the boat, but they are probably too young for the snorkeling. I'd talk about it with the boat crew to see what thoughts they have.
I've never visited with kids that young or seen any there. If they're great swimmers it might work but it might be frightening - depends on the kids. I would talk to the agencies about this because they might have suggestions or age limits.
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