UPDATE: In response to an Us Weekly interview with the brother of Deanna Hummel (seen below), saying he knows his sister is having an affair with 'Jon and Kate Plus 8' dad Jon Gosselin, Deanna has spoken up to People:
Read the whole story on People
"My brother is making this all up," Hummel tells PEOPLE. "He has no credibility ... I can't even stomach the lies he's saying about me."
Hummel continues to deny any sort of romantic relationship with Gosselin, and the elementary school teacher admits that there's been bad blood between her and her brother for a while now. "My brother is very shady," says Hummel. "He has no job. He has a criminal background. He was charged for drug distribution. He's on probation right now."
Jon has ALSO now released a statement to People denying the affair, reading in part:
"These allegations are false and just plain hurtful," Gosselin says in a statement exclusively to PEOPLE. "As I adjust to the attention that comes from being in the public eye, I need to be more careful and aware of who I am associating with and where I am spending my time. But the bottom line is, I did not cheat on Kate.
In the new issue of Us Weekly (on newsstands Wednesday), five people close to the situation - including two relatives of the other woman - confirm that Jon & Kate Plus 8 dad Jon Gosselin, 32, has been having an affair with third grade school teacher Deanna Hummel.
The most explosive blow-by-blow details are revealed by Deanna's older brother - and roommate - Jason, who tells Us Weekly that he is speaking out now to set the record straight and to protect his naive sister.