Miller was struck and killed on North Street in Wilkes-Barre back in December.
Investigators want to look at the Facebook activity of Thomas Letteer Junior, as well as his girlfriend, Abigail Tarver.
The two are persons of interest in the case.
Police seized a red Pontiac grand am from Letteer's family's home last week.
Earlier this week -- police filed warrants to seize their cell phone records.
At this point, there have been no arrests or charges filed.