Sarah and Carl Collier died a violent death in their north Fayette home

Monday because their granddaughter Holly and her girlfriend Sandy wanted

to be "together forever," according to Lt. Col. Bruce Jordan of

the Fayette County Sheriff's Department.

Jordan said Sandy Ketchum had been forbidden from visiting Holly Ann Harvey

at the Collier's home, and he also confirmed that Holly and Sandy were

romantically involved.

"I will tell you that I believe the evidence at trial will be that

the motive was to gain freedom and to be able to stay together forever," Jordan

said.

Sandy sneaked into Holly's basement bedroom Sunday night, and she hid

under Holly's bed when the grandparents came downstairs of the Newton

Plantation home to confront Holly over the smell of marijuana wafting from

the basement, Jordan said.

That's when the deadly struggle began, the chief detective said.

"At some point during that confrontation, Holly stabbed her grandmother

with the knife," Jordan said. Sarah Collier was 73; Carl Collier was

75.

As the Colliers pinned Holly down on the bed, Holly shouted at Sandy, "Why

aren't you helping me?" Jordan said.

Sandy, who is cooperating with police, then came out from beneath the bed

and jumped into the fray, using a knife she had hidden with her, to take

part in fatally stabbing Sarah Collier, Jordan indicated.

Mrs. Collier was still alive when Holly chased her grandfather upstairs

as he tried to escape the melee, Jordan added.

Mr. and Mrs. Collier were stabbed at least 15 times each, Jordan said, choking

up as he described details of the bloody crime scene.

"I believe Sarah [the grandmother] was stabbed many more times than

that," Jordan said, noting that he had not yet seen an autopsy report.

Holly and Sandy telephoned friends about the killings and asked if they

had seen information about it on the news, Jordan said. The "friends" were

mostly people Holly and Sandy had met while at a Regional Youth Detention

Center, Jordan said.

"Once these friends learned they had actually done this, they were

no longer on their side," Jordan said. "... Kids started to tell

their parents what was going on. We had a lot of informants in the first

few hours."

At the crime scene, Jordan said he found a poem with Holly's belongings

that "talked about Holly's depression and that she cried herself

to sleep at night."

Holly and Sandy were both on suicide watch at separate juvenile detention

facilities Tuesday evening, Jordan said.

It is not known if Holly was on medication to possibly treat depression,

but a bottle of prescription medicine was found with her when she was arrested,

Jordan said.

Holly, 15, would have been a freshman at Sandy Creek High School this year

after attending Flat Rock Middle School last year, school officials said.

Sandy, 16, last attended the Fayette County Alternative School in 2003 and

previously attended Fayette Middle School, officials confirmed.

Investigators believe Ketchum lived in the Brooks area, but those minor

details haven't been ironed out as the investigation continued Thursday,

Jordan said. Det. Ethon Harper is the lead investigator on the case, Jordan

added.