Sonesta Great Bay is in P'burg and is adult only
Sonesta Maho is in ... Maho and is a family resort - though I don't think there are that many children, will depend on the time of yr.
Two different hotels in 2 different locations. I would not walk into P'burg at night from the Great Bay location
Maho however is better for nightlife / entertainment within walking distance [go figure, its the family hotel!]
Great Bay does enforce the no children rule [I think 18 becomes an adult]
There are those that say don't go AI on the island, but if it is your 1st visit, why not, use the hotel as a base to explore or occasionally use the facilities
J&B