News of Hawthorne's sudden death broke this morning, sending shock waves through the theatre community.
Read more: Top Kiwi actress dies
Hawthorne starred in 16 ATC productions, spanning more than 20 years. In 1994, she starred as Nina in The Seagull, making her ATC debut. Most recently, she starred as Miss Adelaide in Guys & Dolls, opposite Shane Cortese.
In a statement, McColl said: "My enduring image of Sophia will always be her bursting onto the stage, in Michael Hurst's production of Romeo and Juliet wearing a paint-stained white shirt, her thick raven hair flying - her laugh, her smile, her big dark eyes glistening with excitement.
"This was no copycat performance or museum piece Shakespeare but a wholly original, transcendental and modern interpretation of Juliet. What was so extraordinary was her thorough understanding and embodiment of the poetry. Sophia made the language sing, as if it has been written yesterday. She was sixteen years old."
Born into an Auckland theatre dynasty, acting was always in Sophia Hawthorne's blood.
Her father, Raymond, is one of the country's most acclaimed actors and directors. Her mother, Elizabeth, an icon of New Zealand's stage and screen.
Growing up, she was entranced by what her parents and their friends did on stage.
The Hawthornes have asked for privacy as news of Sophia's death spreads, with tributes remembering "a wonderfully spirited woman".
Fellow actors, Jennifer Ward-Lealand and Michael Hurst said it was terribly sad news for the acting community.
"Both because we have lost one of our own but also for the impact this will have on our dear colleagues and friends, Sophia's mother, Elizabeth, her father, Raymond and sister Emmeline. She shone so very brightly in so many productions."
Michael Hurst recalled directing Sophia in a 1993 production of Romeo and Juliet when she was just 16 years old and still at school.
"She played Juliet and she did it so brilliantly. She did things, put things into the role, that I could never have told her to do or directed; it came by instinct and was stunning to watch."
Actor Shane Cortese said: "I'm numb right now, Today the acting community lost a member of our family. I can't help but feel privileged to be the last to sing duets with her, to make people laugh with her, we will miss her. I will miss her."
Another colleague said: "She was regarded as a very fine actress, with great integrity and depth. She had a luminous presence and lit up the stage, leaving audiences profoundly moved. I am shocked and devastated."
A spokeswoman for her agent, Gail Cowan Management, said they would not be commenting today.
Posting on the Herald's Facebook page, a school friend of Hawthorne wrote: "[I] recall how she promised to make her own costume for the school show, which was conveniently not quite ready every time there was a rehearsal - until it was a bit too late to change, then behold Madonna style cone cup bodice! Still makes me smile about it 25 years later!"
No further details relating to her death are known at this time.
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- nzherald.co.nz