Multiple orders on different accounts in one go possible?

Hi everyone,
i have 4 of my relatives having trading accounts with one brokerage firm. I want to know whether there are any technology or method available to place an order(buy or sell) for all of them in one go. What i mean is, without placing individual orders for each of them one after another i wish to pass one command that will place order for each of them automatically. Anybody know?. please help me.
sincerely yours.
Murugan.s