They are seeking an injunction at the High Court in Christchurch and will be in court in August.
Mr Pooley's sister Frances also launched a petition on change.org, "To keep our brother Jamie Pooley at rest".
"We are currently facing the High Court of New Zealand to keep our brother's body buried where he is in Christchurch," she wrote.
"It has been an emotionally upsetting time for all and we ask that you sign our petition in support of our family."
However, the petition was removed at the weekend, after it had received 275 supporters and started to be shared on social media.
"It's gone far enough," Ms Pooley, 34, told NZME News Service yesterday, explaining why the petition was taken down. "We just wanted people to know what was happening."
A spokeswoman for the Pooley family said they don't want Mr Pooley disturbed.
"It just seems right to leave him where he is," she said. "As far as we're concerned he's been laid to rest."
When the family first heard of the partner's desire to exhume him late last year, they were stunned.
"It definitely came out of the blue," the spokeswoman said.
The question of cremation never arose when Mr Pooley's funeral was being planned, the family said, adding that cremation goes against both Maori and Catholic customs.
"We're not saying it's never done, but the protocols around that are quite tricky and, given that he is in the ground already, trying to reverse that makes it far more complicated than if it was to happen at the time," the spokeswoman said.
The family also face uncertainty over what would happen to the ashes if he was cremated. While the situation has given the Pooley family "much angst and distress", they also want to treat Mr Pooley's partner, and her views, with "respect and dignity".
Daniel Pooley said his brother's body was "very tapu".
"This issue is the reason we have not been able to give him an unveiling," he said.
But he added: "The other party in this situation is also trying to do what is right out of love but we want him here and believe it's the best place for him."
The online petition attracted many heartfelt messages of support for the Pooley family before it was removed.
Most supporters said Mr Pooley's body should not be touched.
"No family should have to endure what the Pooley family have. Why would anyone want to move Jamie away from his family. Leave Jamie to R.I.P," said Henry Soli.
Tina Bennett wrote: "Nobody should have to go through this trauma. He is at rest now and has been for some time. It is where he should stay."
Mr Pooley's partner was not available for comment.
The case has parallels with the long-running legal battle over the body of James Takamore.
Mr Takamore died in 2007 and was due to be buried in Christchurch.
But his Tuhoe whanau allegedly snatched his body, claiming Maori custom. They buried him at Kutarere Marae alongside other relatives in the Bay of Plenty, against the wishes of Mr Takamore's long-time partner, Denise Clarke, who is Pakeha.
In 2012, the Supreme Court ruled that Ms Clarke could choose where he should be buried.
Earlier this month, the eight-year legal battle was finally resolved with behind-closed-doors mediation.
