Hi there, Thomas!
Welcome to the Disney Parks Moms Panel. First, I'd like to thank your brother for his service to our country.
The
specially priced tickets offered to active duty and retired members of the U.S. military are one of the best discounts available at the Disneyland Resort. These tickets have a very specific usage policy, and unfortunately your brother (or his spouse if applicable) will need to be present and using one of the tickets that he purchased with you. Anyone using the military tickets purchased at a base ticket office has to be present with the active duty sponsor when they enter the Disneyland Resort on their first visit with the ticket. After these tickets are activated with the military sponsor, the rest of the party can come and go independently from either of the parks for the remainder of the ticket.
I'm glad you brought your question here before trying to use these tickets at the Disneyland Resort as you would be denied entry with them if your brother was not present. I have heard of this happening many times as these tickets have a very strict policy.
Before your trip, I recommend
purchasing tickets online or using the Disneyland app. Keep in mind that as you purchase longer ticket lengths, the price per day actually decreases making it more cost-effective to take trips for multiple days.
I hope this helps, and feel free to return if you have any other questions. Have a magical day!
-Jennifer