Tammy Lea Marihugh was born in Los Angeles to part-time Hollywood stand-in, Malcolm Marihugh and his wife, Ellie, a former bank clerk, both of whom encouraged and helped their daughter's career so that by the time she was six, Marihugh had earned about S35,000 from winning child beauty contests, working as a model and appearing on TV. At four, Ellie took Tammy to a local photographer for some photos to send to her family back in Minot, ND. The photographer thought Tammy was so photogenic that he offered free pictures whenever she wanted them if he could use Tammy's photos for his own ads. Ellie agreed and Tammy's photo began appearing in several local Los Angeles newspapers. In December 1957, she won a TV Shirley Temple Smile contest. She was then offered a bit part in Playhouse 90 on CBS, where she recalled making $200 "just for smiling into the camera." In 1958, nearly 209,000 children entered photos for the "Howdy Doody" TV Show Smile Contest, and Tammy won, with a prize of $10,000. She toured the country, appeared several times on NBC, and posed for magazine covers. During October and November of 1958, she appeared several times on the popular Candid Camera-style show, People Are Funny, hosted by Art Linklater. On the show, she was given thousands of dollars in play money, which on one episode she took to various stores trying to buy her father a 50-cent gift and on another, she tried to give away a kitten in public but found it hard to do so. She became very popular from these appearances and in April 1959, she joined the cast of The Bob Cummings Show in its final season with a contract paying $500 per episode. She appeared at the 1960 PATSY Awards, representing Asta, the dog from the 1957-1959 TV series The Thin Man. She soon began to get movie offers and debuted on the theatrical screen in 1960's The Last Voyage, playing the daughter to parents Robert Stack and Dorothy Malone. In June of 1960, Tammy was anointed "Little Miss Hot Dog", symbolizing the July celebration sponsored by the National Hot Dog Month Council. She became the youngest "Miss Hot Dog" in history. In December of that year, she became her parent's landlord when a judge approved her buying a six-room house for $16,000 near the MGM Studio, where she was signed to a seven-year contract making $500-700 weekly. Producer George Pal personally recommended her for the part of Gretel in The Wonderful World of the Brothers Grimm. She was instead cast as Pauline Grimm, Wilhelm Grimm's daughter. This was to be Tammy's final movie appearance and by the mid-1960's, she stopped appearing on TV as well. After a 1964 guest appearance on the CBS sitcom My Three Sons, it was five years later until her next and final acting role, also on My Three Sons, in a 1969 episode.

1961