A 30-year-old woman has become the second person charged over the alleged shooting murder of Sydney teenager Brayden Dillon.
Homicide detectives arrested the woman at Blacktown, in the city's west, about 2pm Wednesday as Brayden's friends were preparing to mark what would have been his 16th birthday.
The teenager was allegedly shot at close range in his bed after a masked intruder smashed his way into the family's Glenfield home early on Good Friday.
He died in hospital later that day.
Friends and family members marked Brayden's "sweet 16th" by candlelight at a well-known footbridge on Wednesday evening.
During the solemn gathering, the group tied balloons, flowers and pictures of the 15-year-old to the East Hills bridge after organising the event on social media.
Rows of candles lined each side of the path as about 30 of Brayden's friends sang Happy Birthday and shared drinks to celebrate his short life.
"Happy Birthday Bray," one woman said as a bunch of blue and purple helium balloons was released into the sky.
The bridge donned messages of support, including "RIP Brayden" and "I love you".
It is becoming a meeting spot for the teen's friends who have struggled to come to terms with his sudden death.
The alleged execution has been described by senior detectives as callous and calculated.
The woman, who was charged with murder, was refused bail and will appear in Blacktown Local Court on Thursday.
On Monday police made their first major breakthrough, arresting 26-year-old Conrad Craig and also charging him with Brayden's murder.
It came less than 24-hours after detectives made a public appeal for information about a suspected getaway car identified from CCTV footage.
The vehicle was found in an underground car park at Jamisontown on Tuesday afternoon and taken for forensic examination.
Craig's matter was adjourned earlier that day and he will next appear in Blacktown Local Court on August 23.