Matt Sandusky's name came up during testimony from one of the alleged victims.
The accuser talked about what occurred after he played racquetball once with Jerry and Matt Sandusky.
"Matt went into the shower, and then me and Jerry came in ... he started pumping his hand full of soap, like he was going to throw it. Matt got out ... he went to another shower [area]."
The witness, the first accuser to take the stand, said Matt Sandusky looked "nervous" when he saw that Jerry Sandusky was about to start a soap fight.
According to several of the alleged victims, Jerry Sandusky would often use shower "soap fights" as a prelude to inappropriate sexual contact.
In his 2001 autobiography, "Touched," Jerry Sandusky wrote about his relationship with Matt Sandusky, who he met through Second Mile when the youth was 7 or 8.
"He would visit our house occasionally, but he was never one to get very attached to anyone. He would stand off in the corner somewhere and watch as I would be wrestling with the other kids. He became an instant challenge for me," Sandusky wrote. "I didn't want to see him go through life by himself at such a young age. I didn't want to lose him to whatever other fates might have awaited him, so I kept trying and trying to pull him in."
Sandusky detailed the youth's discipline problems and struggles, ultimately becoming close to his new family.
"He had the strength and the courage to stay loyal to us even when we weren't sure what would happen," Sandusky wrote. "He could have hurt us. He could have driven us out of his life, but he didn't. And that will always mean the world to us."
Meanwhile, a man who claims he was repeatedly sexually abused by Sandusky while a child spoke out Thursday.
"He (once) told me if I ever said anything that nobody was going to believe me and he would get my dad fired from Penn State," Travis Weaver, 30, told NBC's "Rock Center with Brian Williams."
Weaver did not testify in Sandusky's trial, but did file a civil action against the former coach.
Weaver's attorney, Marci Hamilton, told CNN, "Travis's story fits in with other survivors, but also Matt Sandusky."
She said her client at first thought he was the only victim.
"When he found out there were others, he was in real misery," Hamilton said, adding Sandusky tried to adopt Weaver.