do i need to bring in infant carrier and toddler carseat for shuttle to miami port? i will be traveling from PA.

I am not sure you need the car seat. It's better to directly call and ask. Potential liabilities might force so e protocols and procedures

I am planning to drive from pa to the cruise parking lot. On your 15 pass shuttle, do kids usually need a car seat for the short trip?

The shuttle is a 15 passenger van.