How much should a kid pay to travel as a Spirit unaccompanied minor?

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 Children under 4 are not permitted to fly by themselves. They should be joined by a second guest who is at least 15 years old.  Spirit Unaccompanied Minor Fee  is  $100 each trip for each traveler with Soul Carriers. The costs also cover the snacks and drinks that will be provided for the child during the flight. For a roundtrip flight, unaccompanied minor assistance costs $200.