Rome (CNN) -- The family of a Minnesota couple that remains unaccounted for after a massive cruise ship ran aground off an Italian island last month plans to hold a memorial service to celebrate their lives.
Gerald and Barbara Heil have been missing since the Costa Concordia hit rocks and ran aground off Giglio Island on January 13.
Relatives said they accept the decision to call off the search for missing passengers. A service is planned in the coming weeks, the family said in a statement.
"We are certainly disheartened to hear this news but understand and accept the decision to bring the search operation to a halt," the statement on the family website said. "We cannot express enough our sincere gratitude to all those involved in the search and rescue effort."
Their daughter said her mother had not traveled much until her father retired from the Minnesota Department of Agriculture.
"They'd been going a lot of places," Sarah Heil told Chicago's WBBM Radio. "I was really happy because they deserved to go on this awesome trip they had planned."
The Heils are from the Minneapolis-St. Paul area.
A total of 15 people remain missing after the cruise ship's collision off the coast of Tuscany with about 4,200 people aboard.
Seventeen bodies have been recovered.
Franco Schettino, captain of the Costa Concordia, said after the ship hit the rocks, he ran it aground to keep it from sinking and limit the tilting. It came to rest on its right side with roughly 50% of the ship under water. It is currently rotated nearly 90 degrees.
Salvage operations in the part of the ship above the water line will continue, salvage officials said, along with searches around the wreck.
Underwater operations have previously been temporarily suspended for safety reasons, but have always resumed. Technical experts are advising they come to a permanent end.
Schettino is under house arrest on suspicion of manslaughter, causing a shipwreck and abandoning ship while passengers were still aboard. He denies the charges, saying his actions saved lives.
Schettino has admitted to prosecutors, defense attorneys and a judge that he made a "mistake" in colliding with the rocks off shore. But he has brushed aside suggestions that he was going too fast, as prosecutors allege.
The lead prosecutor is asking that Schettino be sent back to jail. A hearing has been scheduled for Monday.
However, Schettino's lawyer says his client should be released from house arrest.
A number of survivors have filed lawsuits against the company that ran the cruise, Costa Cruises.
Costa has announced it is offering each of about 3,200 passengers who had been aboard the vessel a lump sum of 11,000 euros ($14,400), in compensation for their loss of property and emotional distress, as well as a refund of costs associated with the cruise.
Separate agreements will be reached with those passengers who were injured and needed treatment at the scene and with the families of those who died, Costa said.
CNN's Hada Messia and Nigel Walwyn contributed to this report