Robert Downey Jr. and his wife Susan welcomed their son Exton Elias into the world at 7:24 a.m. on Tuesday, reps have told Us Weekly.

Exton Elias is the first child for the 46-year-old The Avengers actor and his producer wife Susan, 38. They got married in 2005. The baby is a healthy 7 pounds 5 ounce bundle of joy who is said to measure 20 inches long.  Downey already has an 18-year-old son named Indio, with his ex-wife Deborah Falconer.

Downey previously revealed that he was expecting a son. However, he was rather tight-lipped on the name he and his wife chose for their first child together.

If I told you the name, then [my wife] would lop off my head with a machete, the actor joked.

Neither Downey nor his wife Susan has explained why they have decided to name their child Exton Elias. But a quick Google search shows that Exton is a place in West Whiteland Township in Chester County, Pa.

Indio's name is a location. It is a city in Riverside County, Calif.

Here are 14 other funny celebrity baby names (in no particular order):

1. Blue Ivy: The name hip hop's hottest couple Beyonce and Jay-Z gave to their daughter who was born last month.

2. Kal-El: The name of actor Nicolas cage's son. Cage's son is named after Superman.

3. Jermasjesty: This is name of Jermaine Jackson gave to his fourth child.

4. Pilot Inspektor: My Name is Earl actor Jason lee told Entertainment Weekly that he name his son after a song on the Grandaddy's 2000 album titled the Sophtware Slump.

5. Apple: The name Gwyneth Paltrow and Chris Martin from Coldplay gave to their daughter.

6. Moxie Crimefighter: Magician Penn Jillette said his daughter's name Moxie was created by an American for the first national soft drink and then went on to mean chutzpah, and that's nice, quoted a report in The New York Times.

7. Kyd: The name of David Duchovny and Tea Leoni's child.

8. Nakoa-Wolf: If it wasn't weird enough that Lisa Bonet, a former Cosby Show star changed her name to Lilakoi Moon, she and her actor husband Jason Momoa named their son Nakoa-Wolf Manakauapo Namakaeha Momoa .

9. Memphis Eve: U2's Bono named his daughter Memphis Eve when she was born in 1991.

10. Prince Blanket Michael Jackson II: He is the third child for the king of pop and was born in 2002. Commonly called Blanket, Prince Michael was carried by a surrogate mother.

11. Diva Thin Muffin Pigeen: She is the youngest daughter of musician Frank Zappa. He also name another of his child Moon Unit.

12. Blue Angel: Is the name U2's guitarist gave to one of his three children with wife Aislinn O'Sulliavn.

13. Audio Science: This is the name of actress Shannyn Sossamon's son with children book's author Dallas Clayton.

14. Tu Morrow: Actor Rob Morrow, known for playing the character Don Eppes on Numb3rs, married actress Debbon Ayer in 1998 and have a daughter they named Tu Morrow. The girl's full name is Tu Simone Ayer Morrow.