With a 2 year old, I would take the ferry from the airport, yes it's double the cost, but maybe 10-12 people total, and it's quick, more like a large speed boat ride. Parking is next door at the old terminal and it's free. Then just have a taxi driver take you to whatever beach you want, you can also ask them for a quick island tour as well. Just my thoughts. Not dealing with Marigot was most enjoyable!!
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