Lilie James was found dead in the gym bathroom just before midnight on Wednesday night.

The scene officers found was "confronting", police told reporters. Ms James died from severe head injuries, they said.

Two days later, the body of the man suspected of killing her was pulled from the water seven miles from the school.

Ms James's grandmother has now spoken about her granddaughter. Barbara Adelt told 2GB radio on Monday that the family "just can't understand why this would happen to her".

"Some people come into the world, I think, they are so special, and they don't stay long. Now, I think that was my granddaughter," she said.

"She was so kind to everybody else. She was the most loyal person. Very loyal. She's her mum's daughter.

"She was so full of life. She never stopped. She went to university, she worked four and a half days a week, she coached swimming, she coached water polo."

Ms James was a water polo coach at St Andrew's Cathedral school, a private school in the centre of Sydney.

School principal Dr Julie McGonigle, wrote to students' families in the wake of the tragedy.

"She was full of vitality, energy, enthusiasm and a natural fit in our community," local media reported Dr McGonigle as saying.

"There are no words for what has occurred. It is like entering a foreign land which possesses no words."

The school was shut for two days last week as police combed the grounds. It reopened on Monday, the entrance carpeted with flowers.

Body found at base of cliffs

Two days after Ms James' death, the body of the only suspect was found at the base of nearby cliffs.

Paul Thijssen, a 24-year-old Dutch national, was also a sports coach and assistant at the school.

He was in a brief relationship with Ms James that recently ended, according to local media.

Thijssen reportedly called police four hours after her death and told them where to find the body.

Police traced the call to The Gap at Vaucluse, a clifftop below which Thijssen's body was later found.

A second crime scene was established there as police found items linked to the homicide - reportedly the hammer allegedly used to murder Ms James.

Family and friends 'broken forever'

Ms James family described her as "vibrant, outgoing, and very much loved by her family and friends".

"We are devastated and heartbroken," they said in a statement.

A fundraising page set up by Daniel Makovec, who described himself as a close family friend, has raised close to $20,000 (£10,500) for the family.

He wrote: "Everyone who has been graced with the presence of Lilie will be broken forever.

"With tears streaming, numb with disbelief, this new journey is now a long one for the family."

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Violence against women in Australia

Ms James is the 41st woman to die allegedly as a result of gendered violence in Australia this year, according to the Counting Dead Women project.

New South Wales domestic violence prevention minister Jodie Harrison urged people to call out misogynistic behaviour in the wake of Ms James's death.

"It's up to everybody to call out inappropriate behaviour. That's really the start of a lack of safety for women and children," she told Guardian Australia.

"It's up to every single one of us. Government can fund programs but unless individuals take responsibility for themselves, that government funding will be wasted."