He, his three young daughters, and his wife were all sleeping. It is the latest attack against his family.
"I don't even want to come outside anymore, because I don't know what's going to happen to me," Granby says.
According to Granby, it all started about two weeks ago when someone spray painted a swastika on his family's van in their driveway.
A few days later, the side mirror was broken off.
On the same day that the rock was thrown through the window, their tires were slashed. Granby then moved the van around the corner because he was afraid it may be vandalized again.
"I've been up for a couple of nights just looking out for them hopefully I'll catch them," said Granby.
Suffolk police say they are investigating the swastika incident as a hate crime. They have also taken reports on the other incidents.
Granby says that he has no reason to believe that anyone would be upset with him or his family. He thinks it may be racially motivated.
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