His son, he said, had attended a gathering for potential new members at the fraternity house on the evening of Jan. 9. After the event ended, he remained at the house, socializing with a small group of friends, the father said. His son was last seen at 12:45 a.m.
Hartford suffered multiple skull and facial fractures, severe brain trauma, a broken wrist and optical nerve damage, he said.
The doctor told him the injuries were consistent with a fall from about 15 to 20 feet, he said. University of Pennsylvania detectives who investigated told him they believe Hartford either fell from the window or had been locked out and was climbing up to get in the window.
Penn officials declined to release any information about the fall and issued a one-sentence statement.
"We are deeply saddened by Tom's tragic death, and our thoughts and prayers are with his family and friends at this very difficult time," said Stephen J. MacCarthy, vice president for university communications.
The fraternity also issued a statement, noting that Hartford was a former member.
"While he was no longer affiliated with the chapter, he remained close with many of the undergraduate members," said Brian Warren Jr., executive director. "Our thoughts and prayers go out to his family and friends."
Hartford's father said his son had drinks that evening but was not intoxicated. A child support system investigator for Monroe County, he said he doesn't blame the university or anyone and has no plans to sue.
"They've been great to us," he said of the university. "It was just a tragic accident in my mind."
An avid soccer player and skier, Hartford was a well-liked, positive young man, majoring in cognitive science, his father said. Fifty fraternity brothers came to visit him at the hospital on Tuesday.
"They came to say goodbye," Hartford said.
The viewing will be at Clark Funeral Home in Stroudsburg on Friday. Services will be held Saturday at Reeders United Methodist Church where Hartford was a member of the youth group.
Contact Susan Snyder at 215-854-4693 or firstname.lastname@example.org, or follow on Twitter @ssnyderinq