Zakky!!!

That's what Mara calls Z. You can hear delighted screams of, "Zakky!" as soon as she catches sight of him. Sometimes, she hasn't even caught sight of him, she can just hear him from outside. And if Zach hears her playing out on the deck, he runs and pounds on the sliding door, yelling "Ow-sigh, Ow-sigh, Mara, Mara, Mara!" Until we let him out to see her.