Rome (CNN) -- A day before American Amanda Knox's appeal of her murder conviction resumes in an Italian appeals court, the sister of slaying victim Meredith Kercher vowed to keep fighting for justice on her behalf.
"Anyone reading this or following this case, please remember our beautiful Meredith," Stephanie Kercher said in a statement distributed Sunday by attorney Francesco Maresca. "... Amongst the media frenzy that has developed throughout, Meredith has been forgotten because she is no longer with us, yet this should be about her and what really happened on that tragic evening."
Knox and her ex-boyfriend, Raffaele Sollecito, were convicted in the 2007 death of Kercher, 21. Kercher, a British exchange student, was found dead in the villa she and Knox rented in the central Italian university town of Perugia, seminaked and with her throat slashed. Knox was sentenced to 26 years in prison, Sollecito to 25.
In July, the Italian appeals court heard testimony about new DNA analysis that may call Knox's conviction into question. The proceeding will resume Monday.
At trial, authorities testified that a knife found in Sollecito's home had traces of Knox's genetic material on the handle and Kercher's in a tiny groove on the blade. DNA on Kercher's bra was also traced to Sollecito.
Those results have been contested by two court-appointed forensic experts, professors Carla Vecchiotti and Stefano Conti. Vecchiotti testified in July that the knife tested negative for blood and the amount of DNA said to be Kercher's was so low, it could not be examined again with any conclusions. Vecchiotti and Conti also said there was no evidence the knife had been "thoroughly washed," as prosecutors argued during the trial.
Prosecutor Manuela Comodi questioned Vecchiotti regarding the standard sufficient quantity of DNA for valid testing, suggesting experts differ on the amount.
Meanwhile, they said, the clasp from Kercher's bloodied bra, which allegedly contained Sollecito's DNA, was "dirty" and had been allowed to rust, making further testing futile. The evidence, the two argued, should be "inadmissible."
"Over the last week, we have waited anxiously and with great concern as the rumours surrounding the original DNA evidence findings are spreading," Stephanie Kercher said in the statement. It's difficult for Kercher's family to understand how the evidence, so carefully developed and presented at trial, could be deemed irrelevant, she said, and also to understand how a small amount could be useless when there is no determination of how much should be present.
Knox's defense seems "to focus and rely heavily on these two pieces of DNA evidence, but can we just remember for a moment what this case is actually about: my sister, a daughter brutally and selfishly taken from us nearing four years ago ... not a single day goes by that we can grasp any peace or closure."
She urged the public to remember the blood-splattered crime scene as well as 10,000 pages of evidence presented in the case.
"We still have confidence in the Perugia police and every faith in all those involved in court and the investigation," Stephanie Kercher said. Her family is asking that the appeals court assess each piece of evidence, "both scientific and circumstantial, as well as any witnesses who have taken the stand independently of any other information or media."
The Kercher family has not forgotten Meredith, she said, "and we will continue our fight for justice with the continued support of our lawyer Francesco Maresca and his team, the police and prosecution and all those involved in Italy as well as everyone all over the world who still thinks of us and Mez."
She said the family would like to work with the University in Perugia to offer a yearly place to a student in Meredith's name. "Meredith loved Italy and its people and she wanted to immerse herself in the culture," her sister said. "We are well aware of the impact this has had on the city and feel it would be an appropriate way of remembering Meredith in the beautiful place she left us to study.
"Please do not let Meredith die in vain," Stephanie Kercher said. "Her courage and strength fight on and we will seek justice so she can rest in peace." Her sister, she said, put up a fight for her life and did not give up, "and we will not give up now."
A third defendant, small-time drug dealer Rudy Guede, an immigrant from the Ivory Coast, was also jailed in connection with Kercher's death. He was sentenced to 30 years for murder and sexual violence following a fast-track trial in 2008, but his sentence was later cut to 16 years.
CNN's Hada Messia contributed to this report.