The 39-year-old went missing last October under mysterious circumstances.
Los Angeles Police Department detectives told family and friends that an incident at a downtown L.A. apartment building in October resulted in her death.
Questions remain about why Planck was at that high-rise where her dog was found wandering on an upper floor.
A search at a Castaic landfill for her remains didn't turn up anything conclusive.
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Planck's friends have set up a website in her honor. They're now hoping people will do and share acts of kindness in Planck's memory.
The website talks about the case and Planck's life. Friends ask that visitors email in their random acts of kindness. They plan to post those emails on the website.