Some of you have asked a number of questions which I can answer.
rives21-We rented from Thrifty and found they made arrangements for a replacement car on Nevis. All we did was have the Marriott call them, and tell them what ferry we were planning to take, and our car number; and they had a van available for us for the day, free of charge when we arrived at Nevis. I parked our car at the St. Kitts ferry at about 7:30 AM, and then simply got into the car upon return. I too saw Thrifty's brochures featuring the Suzuki, but when I received the car at their facility, returned the car at their facility, and looked to see what they had on Nevis, I did not see that they had any Suzuki's, other than Jeeps. The Jeeps were in demand by those arriving by day from the ships docking early in the AM. I had some sort of intermediate-sized Japanese cars (I had a flat tire, and they came out and replaced the car).
As for children-friendly, it was difficult to judge, as I didn't see many kids. They have a long beach, and 3 swimming pools, so I suspect that the anticipate lots of kids.

We flew AA into SXM (Sint Maarten) and then Winair for a 20 minute flight. USAir has a flight thru Philly once a week, and they had many angry passengers who either arrived early next morming or late the next evening, as USAir sent their A/C on to St. Kitts without waiting for those passengers racing thru the Philly airport for the connection. Those arriving early next morning had slept in the airport at SJU or stayed overnight at Philly and then flew AA thru SJU.