We stop to check out a group of balloon animals for sale that seem to be alive, twisting into different shapes and colors as we watch. One forms a dachshund that barks out loud, tail wagging. Another becomes a big, round happy face, smiling at us while it changes colors every few seconds. There’s also a dolphin that seems to leap through the air, a bird that flies back and forth, and a T. rex that roars and stomps around. The last one is my favorite. “They’re all programmable,” the vendor says. “You pick the shape and whatever you want it to do or say from dozens of options.” Zoe buys a butterfly that flits around her head, shifting between different sparkling colors, while Trent gets a black cat that curls up on his shoulder and purrs. They can’t take them back to the present with us, b

