Aro
"Such a prize"
I remember myself saying those words almost 2 years ago, when we were giving false information about an immortal child from Irina I think the Denali coven claimed her to be. Young Isabella and Alice would make great guards in the volturi, Isabella could become our source of protection and Alice could be a look out for anything that comes our way.

"Master, what has you so deep in thought there is only one human left from the group, you're usually the one that has first drainage?" Jane said to me.
"Sorry my dear, I was just thinking about how our young Isabella and Alice would be prized guards in our coven." I replied. Jane put her lips into a tight smile, she hasn't been fond of Isabella since she failed to harm her with her ability. "I guess the last human is yours."
I slowly approach the young girl at around age 7, there isn't much blood in the young ones. With one swift movement I sink my teeth into her tiny neck, devouring the sweet taste of blood. Soon her screams die out and everything returns to normal.
I head to my office in the center of the castle and try to find ways to get Isabella and Alice into the volturi, become an alliance with the Cullen's? Then betray? Or something that could start a war?The latter makes more sense to me because the Cullen's will be very suspicious if we become alliances, especially since we tried to kill their little snack, Renesmee, but what would the Cullen's possibly do that could start a war?
Only one way, there has to be a Blood Moon, a myth old as time itself. I must call upon a young witch that doesn't know anything and have them cast a immortality spell and they will soon die, causing a blood moon. Once the deed is done and there is a blood moon child we will end the Cullen Coven and Isabella and Alice shall join me as guards.

"Marcus, my dear brother, call upon a young witch and have her meet me here, in my office after sunset or before sunrise.
"Yes, master, my apologies for speaking out of thought but why would you want a witch especially a young one."
I have to keep this for myself until the time comes for the plan. "Hmm, I figured I was leader Marcus so that is confidential."