Originally Posted by caberg
...As long as my wife gets to him...
This is an assumption, and not by any means a given...
If conditions are marginal, either due to sea state or visibility, then MOB #2 may not be able to find MOB #1. At that point you're now facing having to find and recover two people and not just one, hampered by the fact that now you must do it all alone.
The most successful plan is the one that doesn't include the kid being in the water. Do anything/everything to keep that from happening in the first place. Tethers, leashes, safety netting, duct tape, velcro suits -- whatever works. Keep the kid on the boat and this becomes a moot discussion.