Perhaps log into your Spirit flight like you are thinking of purchasing seats. Notice how many seats are already purchased. It seems to me like many people who fly Spirit choose to purchase seats ahead of time. If the seating is looking very limited you might want to pre-purchase seats to avoid the hassle. Spirit fares are "cheap" because the airline counts on $ from seat assignments and baggage fees.
To answer your question, on one flight, I purchased seats for my husband and two kids, as I did not want the kids to sit alone. I left my seat open to chance and logged into our flight right at the 24 hour mark and luckily, I was assigned near my family. I was ok sitting wherever, though (alone time watching a movie on my iPad). If you want to take a chance, try checking in at exactly the 24 hour mark. Your two seats may (or may not) get assigned near each other. A larger group, probably not. Spirit employees are not known for their customer service, so be prepared if you do get split up. If the computer really splits you up badly, you could try doing curbside check-in (assuming the airport has it - MCO does) as a LAST ditch effort. Kindly ask the agent to look for seats closer together and be prepared to tip generously if you score a seat reassignment. This assumes there are unassigned seats still left on the plane. Worst case is you and your daughter get split up for a short period of time during the flight.
GOOD LUCK!! Enjoy you trip!
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