There is a Belk and Kroger that is very close to Hilton Head Island ResortHilton Head is more remote - aka further from shopping/hospitals/emergency care which may be a factor to consider when traveling with an infant.
Vero Beach is a more compact resort, closer to the resort restaurants, beach, etc. - Hilton Head you'd need to shuttle or walk pretty far to get to the beach (when factoring in a baby). I think its close to a mile
Vero is probably the "easier" option - and in May it will be warmer than SC as far as Ocean temps go
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