On a late-October morning, Julia Kern sat in San Diego, sunlight spilling through the window after cradling her infant nephew. “He’s a cutie for sure,” she laughed. In a few short weeks, she’ll trade baby giggles for the squeak of ski pole baskets on the cold Finnish snow, but the warmth in her voice already says a lot about where she is mentally this Olympic year: grounded, grateful, and still having fun. “It’s been a...