So Kate and Penny headed back outside to try it again. Swim Lesson 2.0 Grabbing up their towels, they walked determinedly toward the water’s edge. Staring out at the expanse of water, the tips of their toes lying against the last inches of grass there, Kate heard Penny take a deep breath, and then another. But this time, she wasn’t the only person nervous of wading inside those cool depths. Kate’s stomach clinched. Because now she knew. She knew just how terrifying a step this all would be for Penny: letting her feet fall against the wet sand, feeling their weight sink against the surface there, letting her body break…