Cobie Smulders

The 'How I Met Your Mother' star was actually diagnosed with ovarian cancer in her early 20s. However, Cobie opted to remain silent about her health scare until she'd been cancer-free for five years. Speaking to Women's Health magazine in 2015, she explained: "Now that I'm five years out, I'm trying to think of it as a positive thing and what can I learn from it."