- 1995 - The Bill Nye the Science Guy episode "Waves" premieres in syndication.
- 2001 - The Lloyd in Space episode "Babysitter Lloyd" premieres on ABC.
- 2006 - The Emperor's New School premieres on Disney Channel with the episode "Peasant for a Day".
- 2008 - The Emperor's New School premieres on Disney Channel with the episode "Auction Action/The Astonishing Kuzco-Man".
- 2013 - The Once Upon a Time episode "Lacey" premieres on ABC.
- 2015 - The Agents of S.H.I.E.L.D. episode "The Frenemy of My Enemy" premieres on ABC.
- 1922 - Buddy Pepper (songwriter, composer, arranger, and actor)
- 1949 - Patti LuPone (actress and singer)
- 1951 - Tony Danza (actor, television personality, tap dancer, boxer, and teacher)
- 1958 - Andie MacDowell (model and actress)
- 1959 - Robert Smith (singer-songwriter, musician, and record producer)
- 1961 - Cathy Cavadini (actress, voice actress, and singer)
- 1974 - John Hasler (actor and voice actor)
- 1979 - James McAvoy (actor and voice actor)
- 1983 - Gugu Mbatha-Raw (actress)
- 1995 - Thomas Doherty (actor)
- 1910 - Mark Twain (author writer, humorist, entrepreneur, publisher, and lecturer)
- 1978 - Thelma Boardman (voice actress and writer)
- 2016 - Prince (singer, songwriter, musician, and actor)
|≪||April 20||Timeline||April 22||≫|
Community content is available under CC-BY-SA unless otherwise noted.