|Age||Around 1 hour|
|Cause of Death||Burned in fire and thrown in a pit of oil|
|Killed by||Dan Smithson|
|Family|| Sil † (mother)|
Stephen Arden † (father)
|Abilities||Long tongue is tipped with sharp spines|
|Played by||Kurtis Burow|
Sil's son grows rapidly and can morph into an alien being like his mother, which is different from Sil's, having spines and limbs growing too fast for the skin to keep up with.
Sil's son has a tongue-tentacle which he inherited from his mother and uses it as a weapon.
It is unknown whether or not he has any regenerative abilities, which he would've inherited from his mother, as he is never seen demonstrating this ability in the film. If he did, his body was destroyed beyond the capacity for regeneration, such as being burned to death.
Although Sil is disease-free, possibly boasting an immune system that is superior to a human's, it's unknown if his DNA was impure and vulnerable to disease, such as pollen, infection as well as genetic decay, according to the third film.
Sil's son was conceived shortly after his mother copulated with the human Dr. Stephen Arden, who didn't recognize Sil on account of her dyed hair. Less than an hour after conception, Sil gives birth to her son in an underground cave and then leaves him alone for a while to protect him from the rest of the team sent to kill them. However, he demonstrates that he has a rapid rate of growth, already appearing as a young child, and exhibits a variation of Sil's tongue, able to attack and eat a rat with it. Much later, he is seen transforming into his alien form. Just as he was going to attack Dan, he is killed by being set on fire and thrown into a pit of oil. His death caused Sil to be angry and attack the team.
- "I felt it!"
- "It's started!"
- —Sil to Stephen when Sil discovers that she became pregnant.
Sil is the biological mother of her son. Sil is an alien-human hybrid created by the Search for Extraterrestrial Intelligence program. Escaping her confines she broke out into Los Angeles where she evolved and fell to her alien instinct to find a suitable male and mate; becoming an intelligent but hyper-sexual predator.
Sil succeeds in seducing Arden they copulate, successfully inseminating and impregnating her. Sil remorselessly kills Arden as the rest of the team discover her being still alive and chase her into the sewer. Sil forced to hide to have her baby. Sil gives birth to her son in an underground cave and then leaves him alone for a while to protect him from the rest of the team sent to kill them. After her son is killed by Dan, Sil becomes angry and attacks the team. Sil tries to kill Preston and Dan but is shot into the oil lake which was set aflame by the baby's corpse. Attempting to escape the flames, Her head is shot by Lennox point blank with a shotgun and thrown back into the fire, successfully killing her.
Dr. Stephen ArdenEdit
- "Now, I know in that some cultures women believe they know that exact moment of conception, but really..."
- —Stephen to Sil when Sil told him that she became pregnant.
Dr. Stephen Arden is the biological father of Sil's son. Sil's son doesn't really have a relationship with Stephen. After Stephen impregnated Sil, he is killed by Sil shortly.
Stephen was an anthropologist member of a team of scientists and specialists led by SETI (Search for Extra Terrestrial Intelligence) head honcho Xavier, which tracks and destroys Sil.
- Sil's son never demonstrated the ability to regenerate from injuries.
- He is one of the shortest-lived, alien/human offspring in the series, with Anne Sampas' offspring living shorter than him.
- His first meal appeared to be a rat.
- In the credits, he was identified as "Baby Boy".
- On the concept art he was named as Boy-Sil and Bil
- He is the first second-generation hybrid of the alien species to be half human.