A Denver family of four found dead at an Aspen home with high levels of carbon monoxide were meeting friends for the holiday weekend, the Pitkin County Sheriff's office said Saturday.Authorities said two adults, a man and a woman, along with a boy and a girl were found dead inside. The victims have been identified as Parker Lofgren, 39, Caroline Lofgren, 42, and their children, Owen, 10, and Sophie, 8. The Lofgrens were visiting Aspen for the holiday weekend.In a joint statement, the parents of Parker and Caroline Lofgren called the deaths "tragic."Caroline Lofgren was involved with several charity boards, including Girls Incorporated of Metro Denver and the Colorado Symphony Orchestra. She also helped raise money for Historic Denver."Caroline was a wonderful mother and her quick wit, strength of character and glowing personality endearing her to many friends," the statement said. Parker Lofgren was a founding partner of the Denver-based St. Charles Capital, an investment bank."He was a true friend socially and philanthropically to Denver, and we will dearly miss his vibrant smile and personality," the statement said.The couples daughter, Sophie, was described as a "exceptional young woman," and their son Owen was a "radiant young man." Sheriff spokeswoman Marie Munday said other Denver friends meeting the family at the house a few miles east of Aspen found them Friday evening.Family and friends discovered the bodies and called 911. When members of the Aspen Volunteer Fire Department arrived at the scene, they discovered carbon monoxide levels to be extremely high and unsafe.A team of technicians determined the house's hot water and snow melting systems malfunctioned. This caused the extreme levels of carbon monoxide in the house.The remains have been sent to Grand Junction for toxicology tests. Results could take up to two weeks.