American Idol Katharine McPhee celebrates David Foster's 68th birthday amid dating rumors 11/04/2017 Katharine McPhee celebrated her rumored boyfriend David Foster's 68th birthday. Read More RELATED NEWS 'American Idol' alum Mandisa's cause of death revealed'American Idol' alum Mandisa dead at age 47Katharine McPhee leaves David Foster tour after "horrible" family tragedy TAGS: American Idol The Real Housewives Katharine McPhee David Foster
