Nichole Schmidt filed the lawsuit against Laundrie's parents for the expenses such as funeral costs and due to the loss of care and comfort that the family has experienced, the news station reported.
WFLA said the lawsuit says Laundrie committed "intentional acts" that resulted in Petito's death.
Laundrie, age 23, was found dead in a Florida nature reserve in October. It was later announced he died from a self-inflicted gunshot wound.
He was the sole person of interest police named in the disappearance of his fiancée, Petito, a 22-year-old from Long Island who disappeared in late August while traveling across the country in her van with Laundrie.
Petito's remains were found in a Wyoming national park on Sunday, Sept. 19.
The FBI previously announced that Laundrie, who also grew up on Long Island, claimed responsibility for Petito's death in a notebook found near his remains.
Read the full report from WFLA here.
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