The WMSR's website says, "Children 2 and under may sit on adult’s laps for the journey and not require a ticket. Children 3 and above will require a ticket. If you do not wish to hold your child in your lap you will be required to purchase a ticket for them regardless of age."
I did not see anything on their site about ages. I would recommend contacting WMSR directly.
Yes. As far as I know each event has child seating rates.
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