The older brother of the 12-year-old boy shot and killed in Mattapan was arraigned Friday on gun charges in connection to the fatal shooting.

Walter Hendrick, 22, of Mattapan, was arraigned at municipal court in Dorchester on charges of improper storage and unlawful possession of a firearm and ammunition. Hendrick is expected to post $2,500 bail and return to court on Sept. 6.

Hendrick’s arrest was announced late Thursday, just hours after the 2:06 p.m. call that sent police to the horrifying scene where a 12-year-old boy was suffering from gunshot wounds inside 35 Fessenden St. in Mattapan. He was rushed by ambulance to a local hospital but pronounced dead there.

It was apartment two in the triple-decker where the alleged crime was purported to have happened, according to a reading of the charges by the clerk in the First Session Courtroom.

There was another person under 21 in the home in addition to the child who was killed, according to the prosecutor. Hendrick is the older brother of the shooting victim.

Defense attorney asks for personal recognizance in this matter, saying that he is processing the grief of losing his brother and his family is in the courtroom in his support.

“They want him home. I think this is something Mr. Hendrick is going to need to process as well,” she said. “This is something the family will make sure he responds to.”

He’s expecting a child next month, he has a pending charge, she added. He has no criminal record, according to both the defense and the prosecution.