Marvin Roberts, 16, of the 3300 block of Sydenham Street, is charged with Murder, Robbery, Carjacking, Criminal Conspiracy, Possession of an Instrument of a Crime, Reckless Endangerment of Another Person, and Numerous Violations of the Uniform Firearms Act.
Roberts was arrested Saturday, two days after 38-year-old Gerard Grandzol was shot and killed near his home.
Roberts is being charged as an adult.
His older brother, 21-year-old Maurice Roberts, is also in police custody.
Police say the brothers went to Center City with the intention of robbing someone. The crime was caught on video, and so was their getaway.
"In almost 29 years, it's one of the most disturbing videos I've ever seen," Philadelphia Police Chief Inspector James Kelly said.
Grandzol was fatally shot just after 8 p.m. Thursday in the 1500 block of Melon Street, where he lived.
Grandzol had just parked the family SUV when two men approached. One was armed with a gun.
Police say the suspects took his wallet and tried to steal his SUV with his 2-year-old daughter inside, but he wouldn't let them. He was shot in the head at point-blank range.
"They wanted the car and he wouldn't give up the car. And they shot him for it," said Philadelphia Police Captain John Ryan.
Neighbors quickly rushed to Grandzol's side.
"By the time we ran up to him, people were bandaging him, holding him," one resident told Action News. "And right in the head, right in the face, there was a pool of blood."
He was rushed by police to Hahnemann University Hospital, where he later died.
A home surveillance system equipped with audio captured the crime, while several surveillance systems along their escape route showed the two running.
SEPTA cameras also recorded the duo entering the Fairmount station shortly after the shooting.
The 16-year-old was arrested on Saturday in Philadelphia. Roberts, his brother, was arrested early Saturday evening in Mount Olive, New Jersey.
Residents were left in shock.
"He loved Philadelphia. He loved Spring Garden," another neighbor said.
That neighbor, who knew Grandzol, did not want to be identified out of fear of retaliation. However, he says he was a member of the Spring Garden Civic Association with Grandzol.
"He was a very strong and active member of this community. A husband and a father was murdered three block from my home," he said. "It was very similar to muggings that have been going on in this neighborhood for at least 12 to 18 months."
The neighbor says what happened Thursday night is the result of a buildup of violence over many months.
"There was a number of serious muggings that started taking place. Primarily they were teenagers attacking men and women."
On Friday a Facebook page titled "Remembering Gerard Grandzol" was formed. On it were many pictures have been posted to celebrate his life.
There was also a post that reads in part: "My brother, Gerard Grandzol, was one of a kind. Charming, witty, always smiling and devising ways to have fun."
Many neighbors say he loved his family, especially his two daughters, more than anything.
Police are now comparing other recent armed robberies to see if they are connected to the brothers. The older brother has several prior arrests.
Grandzol's funeral is set for Wednesday.
A gofundme page has been set up to accept contributions to benefit the victim's family.