Keshia Knight Pulliam Is Named New Brand Ambassador for Hairfinity!! Popular hair vitamin company Hairfinity has just picked up a brand new brand ambassador, Keshia Knight Pulliam who played Rudy from the Cosby Show. This is really a great pairing for the two since Hairfinity is known to produce fast results when it comes to hair growth, and of course Keshia is known for her gorgeous head of hair. Look below to see Keshia working the set for the new campaign for the brand, I can’t wait to see what they come up with!