A statement on behalf of Emma Mhic Mhathúna's family said she was "a wonderful mother, daughter and cherished friend."
Ms Mhic Mhathúna passed away aged 37 on Sunday morning.
From Co Kerry and mother to five children, Ms Mhic Mhathúna was one of the most public campaigners over the CervicalCheck controversy.
In May of this year, she settled her case against the HSE and the US laboratory, Quest Diagnostics for €7.5m.
Ms Mhic Mhathúna was diagnosed with cervical cancer in 2016 after receiving two incorrect smear results in 2013.
In July, she was told that her cancer had spread to her brain, leaving her terminally ill.
The statement from Ms Mhic Mhathúna's family read "her love, her quick wit and infectious smile" were irreplaceable to those closest to her.
"Emma, who battled her illness with great valour, passed away peacefully in the comfort of her family’s loving embrace, in the knowledge that she had helped to shine a light on important issues which affected not just her own life, but lives of many others.
"Emma’s unending and unwavering commitment to her children means that her abiding legacy will be that of a great mother. However, Emma will also be remembered as someone who fought for social justice in an exceptionally selfless way during times of great personal challenge.
"The details of her funeral will be released when confirmed, until that time we respectfully request that the family and friends be afforded the space and time to make the appropriate arrangements."
Tributes have poured in for Ms Mhic Mhathúna from a range of public figures and across social media.
Vicky Phelan, who exposed the cervical cancer scandal, told RTÉ: "There are five children left behind here, with the youngest only two."
She added: "It is very upsetting for everybody, but I suppose in my case I am still dealing with terminal illness and it really brings it home… it is very difficult."
- Digital Desk