I'm hoping to teach my boys to swim soon, but, as they say, "you can lead a horse to water, but you can't make it swim." I'm not sure, therefore, when the 4.5-year-old and the 3-year-old will be pool-safe. And, in the meantime, we'll likely have occasional weekend visits to a friend's summer home that has an unfenced swimming pool.

Hence, my question: Can any of you recommend -- or recommend against -- any particular pool alarms that will provide a third line of defense in case the kids escape our watchful eye, and at the same time disregard our admonitions not to play around the pool unsupervised? Many thanks.