- Dec 2 Jarron Collins, American NBA basketball center, 2001-11 (Utah Jazz and 3 other teams); assistant coach (Golden State Warriors NBA C'ships 2015, 17-18; New Orleans Pelicans), born in Northridge, California
- Dec 2 Jason Collins, American NBA basketball center, 2001-14 (first openly gay athlete to play in any major North American pro sports league; New Jersey Nets, Atlanta Hawks, and 5 other teams), born in Northridge, California
- Dec 2 Maëlle Ricker, Canadian snowboarder (Olympic gold snowboard cross 2010; World C'ship gold 2005, 13), born in North Vancouver, British Columbia
- Dec 5 Marcelo Zalayeta, Uruguayan footballer (Juventus), born in Montevideo, Uruguay
- Dec 5 Olli Jokinen, Finnish ice hockey player, born in Kuopio, Finland
- Dec 6 Chris Başak, American baseball player, born in North Platte, Nebraska
- Dec 6 Darrell Jackson, American NFL wide receiver, born in Dayton, Ohio
- Dec 8 Anwar Siraj, Ethiopian footballer
- Dec 8 John Oster, Welsh footballer, born in Boston, England
- Dec 8 Kate Robinson, American figure skater and ice dancer, born in Peoria, Illinois
- Dec 8 Vernon Wells III, American baseball center fielder (Toronto Blue Jays; 3-time MLB All-Star & Gold Glove), born in Shreveport, Louisiana
- Dec 14 Kim St-Pierre, Canadian ice hockey player, born in Châteauguay, Canada
- Dec 14 Patty Schnyder, Swiss tennis player, born in Basel, Switzerland
- Dec 15 Henrietta Nagyová, Slovakian tennis player (9 WTA, 9 ITF titles), born in Nové Zámky, Slovakia
- Dec 16 Gunter Van Handenhoven, Belgian footballer
- Dec 17 Alex Cintrón, Puerto Rican MLB baseball infielder, 2001-09 (Arizona Diamondbacks, and 3 other teams), and hitting coach, born in Humacao, Puerto Rico
- Dec 17 Chase Utley, American MLB second baseman, 2003-18, 6X All-Star (Philadelphia Phillies, Los Angeles Dodgers), and baseball ambassador, born in Pasadena, California
Manny Pacquiao (45 years old)
Dec 17 Filipino boxer, only fighter in history to win 12 major world titles in 8 different weight divisions and the lineal championship in 5 different weight divisions, born in Kibawe, Bukidnon, Philippines
- Dec 18 Naomi Lang, American ice dancer (with Peter Tchernyshev), born in Arcata, California
- Dec 20 Andrei Markov, Russian ice hockey player, born in Voskresensk, Moscow Oblast, Russia
- Dec 20 Geremi Njitap, Cameroon footballer, born in Bafoussam, Cameroon
- Dec 21 Amber Corwin, American figure skater (1997 National Sr - 5th), born in Harbor City, California
- Dec 23 Andra Davis, American football player, born in Live Oak, Florida
- Dec 23 Víctor Martínez, Venezuelan baseball player, born in Ciudad Bolivar, Venezuela
- Dec 24 Yıldıray Baştürk, Turkish footballer, born in Herne, Germany
- Dec 25 Simon Jones, English cricket fast bowler (18 Tests, 59 wickets, BB 6/53; Glamorgan CCC, Worcestershire CCC, Hampshire CCC), born in Swansea, Wales
- Dec 26 Kaoru Sugayama, Japanese volleyball player, born in Iwanuma, Japan
- Dec 28 Chris Coyne, Australian footballer (Bayswater City SC), born in Brisbane, Australia
- Dec 29 Kieron Dyer, English football player, born in Ipswich, United Kingdom
About December 1978
How Old? 45 years old
Generation: Generation X
Leap Year: No
Chinese Zodiac: Horse
Star Signs: Sagittarius (Nov 22 - Dec 21), Capricorn (Dec 22 - Jan 19)
Baseball Players
Basketball Stars
Boxers
Footballers
NFL Stars
Tennis Champions