[Warning: Potentially Triggering Content] The tragedy surrounding the deaths of legendary filmmaker Rob Reiner and his wife, photographer Michele Singer Reiner, has already felt unbearable, and now there is another deeply sobering development. According to a new report out in TMZ on Monday night, the deceased couple's son Nick Reiner - the man who is suspected by police of killing the pair - is now on suicide watch while in custody following his arrest in connection with their deaths.