Katharine McPhee and David Foster's son Rennie appears to have inherited his parents' love for music! On Tuesday, the 38-year-old songstress shared adorable videos of her one-year-old son singing and playing on the piano on her Instagram Story. The adorable clip only shows Rennie's little legs as he barely reaches over the keys. "I love these chunky thighs," Katharine wrote. The "American Idol" alum also proudly showed off her son's impressive rhythm playing the drums! "Already showing off my child's talents" she wrote.