Cops showed up to the Lohan residence in New York last week ... after a member of the family claimed they were receiving threatening phone calls ... but it wasn't Dina ... or Lindsay ... or Ali ... or Michael Sr. ... or Jr. -- it was the youngest Lohan of them all, 15-year-old Cody.
Law enforcement sources tell TMZ ... Cody called the Nassau County Police Department on Thursday and told officers a mystery caller was blowing up his cell phone and threatening to "harm him."
We're told cops checked out the Lohan home -- looking for anything suspicious -- but we're told they didn't find anything out of the ordinary.
Cody's mom Dina is still in Los Angeles, having attended the Kardashian wedding -- but sources close to the Lohan gang tell us family members are taking the threats very seriously and Cody is under proper care.
Lindsay Lohan's Brother
Cops Investigate Threatening Phone Calls
8/29/2011 4:00 AM PDT BY TMZ STAFF
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