Athena was barking to tell us something important. I finally saw just a tiny bit of yellow between Nanook's front legs. He was hiding Athena's tennis ball from her. Above, you can barely see the tennis ball.
Sneaky Nanook trying to look innocent.	Athena wants her ball back!
Athena is not happy if she can't have a tennis ball to play with. Chew sticks, snacks, toys, whatever she is offered MUST be better to her than a tennis ball before she will trade.