Josh Radnor Ted Mosby Actor Jason Segel Marshall Erikson Actor Neil Patrick Harris Barney Stinson Actor Alyson Hannigan Lily Aldrin Actor Cobie Smulders Robin Sherbatsky Actor Bob Saget Narrator Ashley Williams Victoria Guest Star Michael Trucco Nick Petteruti Guest Star Ned Rolsma Marcus Eriksen Guest Star August Maturo 6-Year-Old Marvin Eriksen Guest Star Nicole Limo Christie Guest Star David Henrie Son Guest Star Lyndsy Fonseca Daughter Guest Star Carter Bays Executive Producer Craig Thomas Executive Producer Matt Kuhn Writer Pamela Fryman Director