| Youngest person to have won an Oscar, Emmy, Tony, and Grammy | 60 |
| Youngest Oscar winner in history | 32 |
| Youngest Oscar winner | 21 |
| Youngest one in "My Three Sons" | 41 |
| Youngest Olympian | 17 |
| Youngest of the three Prozorov sisters | 38 |
| Youngest of the musical Jacksons | 32 |
| Youngest of the Marx Brothers | 29 |
| Youngest of the March sisters | 29 |
| Youngest of the Jetsons | 23 |
| Youngest of the Greek gods | 26 |
| Youngest of the gods | 20 |
| Youngest of the Gabors | 22 |
| Youngest of the Gabor sisters | 29 |
| Youngest of the Culkin brothers | 31 |
| Youngest of the Brontë sisters | 33 |
| Youngest of the Brady girls | 27 |
| Youngest of rock's Hanson brothers | 38 |
| Youngest of five famous brothers | 32 |
| Youngest of Chekhov's "Three Sisters" | 51 |
| Youngest of Alcott's March sisters | 38 |
| Youngest of a zany foursome | 27 |
| Youngest Obama | 14 |
| Youngest NHL player to be inducted into the Hall of Fame | 56 |
| Youngest NHL Hall of Fame inductee | 34 |
| Youngest Munster | 16 |
| Youngest MLB player to hit 600 homers | 37 |
| Youngest member of the 500-homer club | 37 |
| Youngest member of Pooh's crowd | 35 |
| Youngest member of a noted comedy troupe | 40 |
| Youngest member of a 1990s girl group | 37 |
| Youngest Masters champ | 22 |
| Youngest Marx brother | 21 |
| Youngest Marx | 13 |
| Youngest March sister | 21 |
| Youngest March girl | 19 |
| Youngest male tennis player to be No. 1 in the ATP Rankings | 59 |
| Youngest major leaguer in 1994 and 1995 | 39 |
| Youngest major general in U.S. history | 38 |
| Youngest Lincoln | 16 |
| Youngest Ivy League school | 26 |
| Youngest Indy 500 driver | 24 |
| Youngest inductee to the NHL Hall of Fame (31 years old) | 56 |
| Youngest heavyweight champion | 29 |
| Youngest Hall-of-Famer (at age 22) to hit 100 home runs | 55 |
| Youngest group in the Girl Scouts | 33 |
| Youngest Greek god | 18 |
| Youngest golfer to shoot his age (67) in a P.G.A. Tour event | 60 |
| Youngest golfer ever to win a U.S.G.A. adult event (age 13) | 59 |
| Youngest goal scorer in MLS history | 35 |
| Youngest Girl Scouts | 20 |
| Youngest Gabor sister | 21 |
| Youngest Gabor | 14 |
| Youngest French Open champion | 29 |
| Youngest French Open champ | 26 |
| Youngest daughter in the comic strip "Stone Soup" | 59 |
| Youngest Cratchit | 17 |
| Youngest Brontë sister | 25 |
| Youngest Brontë | 18 |
| Youngest British Prime Minister, or island in Hecate Strait | 59 |
| Youngest boxer to win the WBA heavyweight title | 47 |
| Youngest Best Actress Oscar winner, 1986 | 40 |
| Youngest batting champion in MLB history | 40 |
| Youngest announcer, at 25, of an NFL game on network TV | 55 |
| Youngest actor to win a competitive Oscar | 41 |
| Youngest 600-homer man, informally | 34 |
| Youngest "Pride and Prejudice" Bennet sister | 54 |
| Youngest | 8 |
| Younger: Abbr. | 14 |
| Younger, heavy-set, hairy gay man | 33 |
| Younger, as a sister | 20 |
| Younger, as a brother | 21 |
| Younger ____ Springtime | 23 |
| Younger sons | 12 |
| Younger son or brother | 22 |
| Younger son | 11 |
| Younger sister of Venus | 23 |
| Younger sister of the Netherlands' Queen Beatrix | 52 |
| Younger sister of Isabella in a 19th-century novel | 50 |
| Younger sister in "The Taming of the Shrew" | 53 |
| Younger siblings, traditionally | 31 |
| Younger sibling, perhaps | 24 |
| Younger sibling's shout, often | 34 |
| Younger sibling | 15 |
| Younger Reagan boy | 18 |
| Younger quarterbacking son of Archie Manning | 44 |
| Younger Pretenders hit? | 23 |
| Younger partner | 15 |
| Younger or Elder statesman | 26 |
| Younger of the Coen Brothers | 28 |
| Younger Guthrie | 15 |
| Younger daughter of George and Laura | 36 |
| Younger brothers, stereotypically | 33 |
| Younger brother? | 16 |
| Younger brother, say | 20 |
| Younger brother of Poseidon and Hades | 37 |
| Younger brother of George W. and Jeb | 36 |
| Younger brother of Cain and Abel | 32 |
| Younger brother | 15 |
| Younger | 7 |