Matt, as he appears in Joey's Flashback.

Matt is the older brother of Joey Arsenick. He was put down sometime before 30 Days Without An Accident. 

Name Matt Thompson
Age 22
Portrayed by Liam Hemsworth
Gender Male
Hair Blonde
Occupation Older Brother
Family David Thompson(Father,Deceased) Joey Arsenick(Sister)
First Appearance N/A
Status Deceased(Shot by Joey after being bitten)
Series Lifespan N/A
Ethnicity Swedish-American