Children's deaths 'devastating'
The family of three children apparently killed by their father "cannot begin to imagine" what was going through his mind.
The bodies of Sam Fuller, 12, and his sisters Becka, aged eight, and seven-year-old Charlotte were discovered by police at a beauty spot in Shropshire.
It is believed they had been stabbed to death by their father Ceri Fuller, 35, who then fell to his death from a nearby quarry.
West Mercia Police have recovered a knife and one line of inquiry detectives are following is that Mr Fuller killed the children before taking his own life.
David Fuller - Mr Fuller's father and grandfather to the children - released a statement on behalf of his and his daughter-in-law's families through police.
"The Fuller and Tocknell families are devastated by this tragedy," Mr Fuller said.
"Ceri was a gentle, sensitive and intelligent man but also a very private one. He loved his children dearly and they were such a focal point of his life.
"His relationship with each one of them was one of gentleness, involvement and attentive nurturing.
"Sam, Rebecca and Charlie were such charming individuals, brought up in an environment of love.
"We cannot begin to imagine what was going through the mind of this gentle man to drive him to such tragic actions. We would ask all to respect our privacy at this time while we try to come to terms with this terrible loss."