In a private funeral service, Parker, 39, Caroline, 42, Owen, 10, and Sophie, 8, Lofgren were laid to rest at the Good Shepherd Catholic Church in Denver.
The entire family died over the Thanksgiving holiday at a home in Aspen. Friends found their bodies on Nov. 28.
The sheriff's office believes the hot water and snowmelt systems weren't working correctly, and caused extreme levels of carbon monoxide inside the house. Toxicology reports could take up to two weeks, according to Deputy Coroner Dr. Chuck Johnson.
In lieu of flowers, donations can be made to the Summer Scholars Program, Girls Inc. of Denver, Owen and Sophie Lofgren Memorial Fund at St. Anne's Episcopal School or Young Americans Bank.
Family friend Elizabeth Milias is trying to turn the tragedy into action.
"In Aspen and Pitkin County we've begun what we're calling the Lofgren initiative and that is a strengthening and standardization of the building regulations that will specify the installation of carbon monoxide monitors in the home," Milias explained.
She says at an interagency meeting on Thursday, Pitkin County and Aspen officials were working rapidly with first responders to enact an emergency ordinance next week which will require carbon monoxide detectors anywhere anyone sleeps.
Milias has also convinced Ace Hardware stores throughout Colorado to make carbon monoxide detectors available at a discount.
The Consumer Product safety commission estimates that some 80 percent of homes in Colorado and other western states do not have working carbon monoxide detector; more often in homes that are rented than owned.
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