"We know the how; we re trying to figure out the why right now, so we re going to need some time to figure that out," Andover Police Chief Patrick Keefe said.
More than 1,000 students and parents mourned the 12-year-old boy who was killed alongside his mother in their $2 million home by his father in what police have described to be a murder-suicide.
Investigators speculate Andrew Robinson, 56, shot his wife Linda Robinson, 55, and their 12-year-old son Sebastian before turning the gun on himself while inside their around 3 am on Thursday.