- Dec 6 K. D. Aubert, American actress and singer, born in Shreveport, Louisiana
- Dec 7 Shiri Appleby, American actress (Roswell), born in Los Angeles, California
- Dec 8 Ian Somerhalder, American actor (Lost, Vampire Diaries), born in Covington, Louisiana
- Dec 9 Jesse Metcalfe, American actor (Desperate Housewives; John Tucker Must Die), born in Carmel Valley, California
- Dec 10 Summer Phoenix, American actress, born in Winter Park, Florida
- Dec 11 Celine Sciamma, French film director (Tomboy), born in Paris, France
- Dec 12 Monica Bîrlădeanu, Romanian actress, born in Iaşi, Romania
- Dec 17 Riteish Deshmukh, Indian actor and filmmaker (Lai Bhaari; Ek Villian), born in Latur, India
Katie Holmes (45 years old)
Dec 18 American actress (Dawson's Creek, Batman Begins), born in Toledo, Ohio
- Dec 19 Patrick Casey, American screenwriter and actor
- Dec 21 Michael Vitar, American actor (D2, D3, Sunset Grill, Sandlot Kids), born in Los Angeles, California
- Dec 23 Estella Warren, Canadian model and actress, born in Peterborough, Ontario
- Dec 23 Jodie Marsh, British glamour model, born in Brentwood, United Kingdom
- Dec 25 Jeremy Strong, American actor (Succession), born in Boston, Massachusetts
John Legend (45 years old)
Dec 28 American EGOT (Emmy; Grammy; Oscar; and Tony Awards winner), piano player; singer-songwriter ("All Of Me"; "Glory"), producer, actor (Jesus Christ, Superstar), and television personality (The Voice), born in Springfield, Ohio
- Dec 30 Tyrese [Gibson], American R&B singer (Tyrese) and actor (Transformers), born in Watts, Los Angeles, California
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)
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