Momma of 3
My husband is retired AF and he bought tickets for us and all his family at the Shades of Green on our last trip. They only need to see one military id. Your sister in law should have a military id since her husband is in the Coast Guard. She is eligible to buy the tickets also. It doesn't have to be the military member. If She doesn't have a military base close to them, it might be easier for your retired AF brother to buy them for everyone. Since she is eligible for the military tickets, it would be permissible for him to give her the tickets.
It is very easy to buy the tickets at the Shades of Green on property. Where are you staying? Someone on this boards can tell you how to get there.
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