Here we go, looks like a big clue?
"Investigators have been seeking to tie Mr. Heuermann to a DNA profile of Ms. Mack,
whose relatives indicated in recent days that the Suffolk authorities had been in touch with them.
“We’re just processing so many emotions right now,” her father, Edwin Mack, said by phone last week from his southern New Jersey home, adding that he was unsure whether he would attend the Tuesday hearing.'
The defendant, Rex Heuermann, is due in court Tuesday. Investigators have been trying to tie him to other unsolved killings on Long Island.
www.nytimes.com