Vigils are expected to take place in Belfast and Ballymena on Wednesday in tribute to Chloe Mitchell.
A huge search operation was launched after the 21-year-old, from Co Antrim, went missing on June 3.
The search was called off after suspected human remains were discovered in Ballymena.
One man has appeared in court charged with Ms Mitchell’s murder, while a second was charged with assisting an offender.
A vigil in Belfast has been organised at City Hall at 5.30pm on Wednesday.
Brendan McNally, whose sister Natalie died in an attack in Lurgan, Co Armagh, in December, said on Twitter that he hopes people will attend.
“I am urging a strong show out at Belfast City Hall on Wednesday 5.30 PM, as a vigil for the life of Chloe Mitchell,” he wrote.
Charity Turning Point NI is organising a vigil in Ms Mitchell’s home town of Ballymena for later on Wednesday.
Members of the community are invited to gather at 7.30pm in King George’s Park in Harryville.
The charity said the vigil has been organised with the permission of the Mitchell family.
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