"Jamal felt the same about his father as he did about Randy. They were both gone, and each of them had taken a little piece of Mama with them that they couldn't bring back." Chapter Eight what does this quote mean?

In context, this refers to the trust and sadness Mama felt after losing both a husband and a son. She left her husband voluntarily because he was abusive, but inside, the damage had already been done. She lost Randy to the streets, the violence, and the gangs.... something from which he would likely not return.