Poltergeist Trilogy Curse

The "Poltergeist Trilogy Curse" is a curse that is supposedly linked to the film series Poltergeist. In most versions of the urban legend, all the cast members died while in others only four deaths are supposedly connected to the curse. In actuality, only 4 of the actors died, two died unexpectedly, while the other two seemingly died of natural causes. And there was also the fact that other abnormal occurences happened during the filming of the three films. It is unsure that this mean that the curse is true or  it is merely a coincidence.

Variations
The most common origin of the curse comes from the production of the first film. During the pool scene, the producers were believed to have used real skeletons during these scenes since real skeletons were cheaper than buying artificial ones. These skeletons were also used in Poltergeist II. The cast were unnevered when they discovered that the skeletons were real and asked the Native American actor Will Sampson to perform an exorcism on the set. Then there came the deaths of 4 of the cast members.

Dominique Dune (Dana Freeling) died at the age of twenty-two at Cedars-Sinai Medical Center 4 days after her abusive boyfriend beat her into a coma. He was later convicted of manslaughter. This was on November 4, 1982.

Heather O'Rourke (Carol Anne Freeling) died unexpectedly of septic shock on February 1, 1988. She underwent surgery in hopes of saving her life, only for her to die later on. She was 12 years old.

However, there were 2 actors who were expected to die of natural causes, and, therefore, are not really considered affected by the alleged curse. They were Will Sampson (Taylor) and Julian Beck (Reverend Henry Kane).

Julian Beck was diagnosed with cancer and battled it for 18 months. He died on September 14, 1985, at the age of 60.

Will Sampson, the actor who allegedly performed the exorcism on the set of Poltergeist II, died at the age of 53 due to severe pre-operative malnutrition, post-operative kidney failure, and fungal infection.

The mysterious deaths were not the only odd occurences that plagued the sets. Oliver Robbins was reportedly chocked to near-death by the demonic clown toy and was unable to breath. The other people on the set didn't act quickly to this because they thought he was acting. Thankfully, Steven Spielberg was able to pull the possessed toy off of Oliver, and he was able to breath again. During filming on Poltergeist III, actress Zelda Rubinstein received a call that her mother died suddenly. There were also reports on earthquakes during the filming of the third movie. Lastly, a car that was shown exploding in the film was seen burning an entire building and the fire endangered the life of one of the crew members.

From the deaths to the 4 actors, and other abnormal occurences on the film set, could this mean that the film trilogy really was cursed or is everything that happened to the actors and on set merely coincidences?