© Getty Images

Marilyn Monroe -

Marilyn Monroe, one of the most popular sex symbols of the 20th century, never really knew who her father was. Growing up she mostly used her mother's surname, Baker.

© Getty Images

Marilyn Monroe -

Monroe's mother, Gladys Pearl Baker, had two children before Marilyn: son Robert and daughter Berniece, but Marilyn didn't even know she had a sister until she was 12 years old.

© Getty Images

Samuel L. Jackson -

Samuel L. Jackson, who is widely regarded as one of the greatest actors of all time, did actually meet his father, Roy Henry Jackson, but only twice in his life.

© Getty Images

Samuel L. Jackson -

Jackson was raised by his mother in Tennessee, while his father lived away from the family in Missouri. His father eventually died of alcoholism.

© Getty Images

Jack Nicholson -

Prolific actor Jack Nicholson, who is best known for films such as 'The Shining,' was raised by his grandparents. He never knew his father and believed his mother was his sister for years.

© Getty Images 

Jack Nicholson -

Speaking about when he learned his sister was actually his mother Nicholson said it was "a pretty dramatic event, but it wasn't what I'd call traumatizing... I was pretty well psychologically formed."

© Getty Images

50 Cent -

Curtis James Jackson III, or 50 Cent to most of the world, never met his father. For the first few years of his life he was brought up by his mother, Sabrina.

© Getty Images

50 Cent -

After his mother tragically passed away in a fire when he was just eight years old, Jackson was raised by his grandmother. His father never played a part in his upbringing.

© Getty Images

LeBron James -

NBA hero LeBron James was born to a 16-year old single mother, Gloria Marie James, in 1984. His father, who is believed to be Anthony McClelland, was out of the picture.

© Getty Images

LeBron James -

During his early years James's mother struggled to find work and eventually she allowed him to move in with Frank Walker, the football coach who introduced him to basketball.

© Getty Images

Colin Kaepernick -

Football star Colin Kaepernick was given up for adoption by his birth mother, Heidi Russo, when he was six weeks old. The identity of his biological father remains unknown.

© Getty Images

Colin Kaepernick -

In 2013 Russo told MailOnline that she wasn't prepared to share the identity of the quarterback's father and added that he had never acknowledged his son.

© Getty Images

Steve Jobs -

Just like Colin Kaepernick, Apple co-founder Steve Jobs was adopted at a young age and never met his biological father. Unlike Kaepernick, however, the identity of his father is known.

© Getty Images

Steve Jobs -

Jobs's biological father, Abdul Fattah Jandali, was a Syrian immigrant from an Arab Muslim family. He was never accepted by the Catholic family of Jobs's biological mother, Joanne Schieble.

© Getty Images

Jeff Bezos -

Amazon founder Jeff Bezos was born to a 17-year-old mother in 1964. Although his father, Ted Jorgensen, was around for his son's first moments, he left when he had barely turned one.

© Getty Images

Jeff Bezos -

In 1968, when he was four years old, the young Jeff was adopted by his mother's new husband, Miguel "Mike" Bezos. It was at that point that his name was changed from Jorgensen.

© Getty Images

Eric Clapton -

Singer Eric Clapton's mother was just 16 years old when she had him, and he never knew his father. Like Jack Nicholson, he also grew up thinking his mother was his sister.

© Getty Images

Eric Clapton -

In his Grammy-winning song 'My Father's Eyes,' Clapton sings about the father whom he never met, and who had passed away at the age of 65 in 1985.

© Getty Images

Adrian Grenier -

Actor Adrian Grenier, who is best known for his portrayal of character Vincent Chase in the TV series 'Entourage,' was born in New Mexico and raised by a single mother in New York.

© Getty Images

Adrian Grenier -

Grenier was estranged from his father, John Dunbar, while growing up. However, he did reach out and reconnect with him eventually, as told in the documentary 'A Shot in the Dark.'

© Getty Images

Darryl McDaniels -

Musician Darryl McDaniels is a founding member of hip-hop group Run-DMC and is another celebrity who was adopted shortly after he was born.

© Getty Images

Darryl McDaniels -

His mother was unmarried when she gave birth to him and she gave him up to the New York Foundling home. To this day the identities of his birth mother and father are unknown.

© Getty Images

Dave Thomas -

Businessman Dave Thomas, who is best known for founding Wendy's, was adopted at a young age and never knew his biological parents. As an adult he was a well-known advocate for adoption.

© Getty Images

Dave Thomas -

After his adoptive mother sadly passed away when he was just five years old, Thomas spent some time with his grandmother while his father moved around the country looking for work.

© Getty Images

Liv Tyler -

Actress Liv Tyler, who is best known for playing Arwen Undómiel in the 'Lord of the Rings' film trilogy, grew up believing that Todd Rundgren was her father, when in fact her father is Steven Tyler.

© Getty Images

Liv Tyler -

The actress was the product of a short relationship between her mother and the Aerosmith front man, and although she did meet him, it wasn't until she was 10 or 11.

© Getty Images

Mekhi Phifer -

Actor Mekhi Phifer, who played Dr. Greg Pratt in NBC's 'ER,' was raised by his mother, Rhoda Phifer, in a single-parent household and never met his father. 

© Getty Images

Mekhi Phifer -

Very little is known about Phifer's father, who abandoned his mother early on and was absent during his child's upbringing.

Sources: (Ranker) (Daily Mail)

See also: Celebrity stay-at-home dads

© Getty Images