The body of the 13-year-old was discovered on Tuesday evening following a desperate four-day search by residents and police.
She was found less than a mile from her Bosworth Street home in a narrow, densely wooded area which sits at the back of a property between Westfield Lane and Parliament Street.
Police later revealed that the Queen Elizabeth Academy student had died from hanging and they were not treating the death as suspicious.
The 13-year-old stormed out of her home last Saturday evening after a row over chores, shortly after she had returned from a holiday in Cornwall with mum, Kelly Peat (34) and step-father Danny Peat (31).
Today national reports included claims that Amber’s father Adrian Cook, 39, found out on Facebook on Monday that his daughter was missing.
Jennifer Lancaster, Amber’s grandmother, was quoted as saying in The Times: “It’s a disgrace that he had to find out that way.
“It’s such a total waste of a beautiful life, a beautiful girl.”
She also paid tribute to the ‘mischievous, fun and loving’ Amber, speaking on behalf of her son.
Ms Lancaster, who is from Ripley in Derbyshire, said: “I just cannot believe this has happened. The whole family is devastated.
“I can’t imagine what has been so bad that Amber had to take her own life like this.
“I do not believe that she would do this over something so trivial as an argument over chores.
“I’m not going to give up until I find out what happened to Amber.”
According to the reports, Ms Lancaster had last seen Amber on Mother’s Day two years ago before the family moved away and they lost touch.
She was reported as saying: “I think she was upset about not seeing her dad. But I don’t know how things have got to this.”
An inquest into Amber’s death is due to open on Wednesday, June 10, in Nottingham.