Lyndsy Marie Fonseca (born January 7, 1987) is an American actress. She is known for portraying Colleen Carlton on the CBS soap opera The Young and the Restless (2001–05), Ted's daughter on How I Met Your Mother (2005–14), and Alexandra "Alex" Udinov on The CW's hit show Nikita (2010–13). Starting in 2015, she had a recurring role on Marvel's Agent Carter as Angie Martinelli.