"The timing is just mind-boggling," Cusson, 43, said yesterday recalling the Presidents Day incident. "I just feel like God had me there at the exact right time."
If Cusson hadn't gotten the milk, she would have arrived five minutes earlier, been occupied helping her grandmother and may not have noticed Thornhill's internal defibrillator had been activated.
The machine, which goes into action when a person has a heart attack or irregular heartbeat, went off at least three times, attempting to shock his heart back into a normal rhythm.
However, the defibrillator was unable to get his heart working properly again and he had a heart attack, Cusson said.
"Had I been a few steps further away, I might not have heard him," said Cusson, who also lives in Franklin and is a nursing student at MassBay Community College in Framingham. "I called 911. ... His eyes started to roll back. And then he passed out. I kicked the feet out of the chair and then laid him down on the floor and started CPR."
Read more: Franklin woman saves grandfather from heart attack