It's impossible to say, particularly since we don't know all that went on in the family.
Jeffrey Sandusky, 41, has not made any allegation that his father abused him. But such allegations have been made by another son, Matt.
If Jeffrey were simply aware of any abuse committed by his father, whether against his brother or anyone else, that in itself would constitute abuse, said Steven Berkowitz, a child and adolescent psychiatrist at the University of Pennsylvania.
Boys who are sexually abused are roughly 20 percent more likely to grow up and commit sexual abuse themselves, he said.
But that is 20 percent of a fairly small number. The overwhelming majority of abuse victims do not become perpetrators, said Berkowitz, an associate professor of clinical psychiatry at Penn's Perelman School of Medicine.
Exact numbers are hard to come by, in part because some perpetrators of child sexual abuse are never caught. But if, say, 2 out of 100 adults overall commit sexual abuse against a child, that means that among adults who were victimized as children, the number who grow up to commit abuse themselves would be 2.4 out of 100.
Here's what Jeffrey Sandusky had to say about his father in a 2015 interview with bleacherreport.com:
"Dad himself says he had boundary issues, meaning that he'd put a hand around your shoulder, he'd have his hand on my leg," he says. "Can that be taken the wrong way? Yes, and I get it. But he was not doing it to be a creeper, a perv. No, he was doing it to say I care about you."
Both he and his brother were adopted.
One possibility: a victim of abuse may have less impulse control as a result, he said.
Statistics also reveal that the overwhelming majority of perpetrators are familiar faces. Roughly 60 percent of perpetrators are known to the victim but not family members, while 30 percent are related to the victim, according to the U.S. Department of Justice. Just 10 percent are strangers to the child. Many abusers are never reported.
What can parents do?
Parents can be on the lookout for warning signs, Berkowitz said.
A person bent on sexually abusing a child often tries to ingratiate himself with the family of the intended victim, the psychiatrist said.
"Often they have reached out to the family to be helpful or supportive in some way, shape, or form," Berkowitz said. "And while that seems on the surface quite good, you have to wonder, when they're paying special attention to your child, if there's not an ulterior motive."
If, for example, a child is invited to go on a trip with a teacher or coach, a parent can ask questions. Will other adults or chaperones be present? Is the school officially involved?
Another red flag: abrupt changes in behavior could signal that a child has been abused, among other possibilities.
"Irritability, withdrawal, new onset of drug or alcohol abuse, that kind of thing," Berkowitz said.