Former child star who became U.S. ambassador to Czechoslovakia:

Shirley Temple
Shirley Temple Black served as ambassador from 1989-1992. She also served as ambassador to Ghana in 1974.
Source: Toronto Sun, 1/26/1997

 
   
  Child star who played Richie Petrie on the Dick van Dyke show:

Larry Mathews
Mathews played Laura and Rob Petrie's son from 1961-1966. He now does filmwork behind the scenes in California.
Source: Hamilton Spectator, 4/11/2005

 
   
  Child star who played Dennis the Menace on the TV series:

Jay North
North starred on the show from 1959 to 1963. Today, he provides counseling to child and teen stars.
Source: Hamilton Spectator, 4/11/2005

 
   
  Child star who played Eddie Munster on The Munsters:

Butch Patrick
Patrick starred on the show from 1964 to 1966. He still gets acting jobs, and is often invited to speak on talk shows.
Source: Hamilton Spectator, 4/11/2005