For Dorthy Moxley, October is the cruelest month.
When the fall arrives, and the leaves whirl, her anxiety builds up to the final days of the month, when Moxley must mark the anniversary of the savage murder of her daughter Martha.
But this month, for the first time in 23 years, Moxley's anxiety is tinged with nervous excitement as she watches prosecutors track down reluctant grand jury witnesses, and compel them to tell what they know about the killing of the 15-year-old Greenwich, Conn. girl - and the whereabouts of Michael and Thomas Skakel, brothers who lived next door, on the night of the murder.
Testimony remains secret, but pressure on the Skakels is increasing as key witnesses receive grants of immunity and others are forced to testify.
''It certainly is progressing, that's for sure,'' said Dorthy Moxley yesterday, during a telephone interview from her home in a New Jersey suburb. ''It's like a miracle.''
Michael and Thomas Skakel, who both live in Massachusetts now, are the nephews of Ethel Kennedy, widow of Robert F. Kennedy. Both Skakels for years have been repeatedly named as suspects in Moxley's slaying, though no grand jury was ever convened and no charges ever brought. Both, through their attorneys, have repeatedly denied killing Moxley.
Now, however, police are searching for a cousin of the Skakels - James Terrien - who is key to Michael Skakel's version of events on Oct. 30, the night Moxley was clubbed to death with a six-iron and dragged across the lawn between her parents' home and the Skakels's. Skakel has reportedly told police he was at Terrien's house that night.
In addition, prosecutors granted immunity to a former tutor for the Skakel brothers, Kenneth Littleton, who had refused to testify earlier, exercising his Fifth Amendment right. But after negotiations with Connecticut State's Attorney Jonathan C. Benedict, Littleton, who was in the Skakel home the night Moxley was killed, testified. He did so with the understanding that he could not be prosecuted for any crime connected to the case except perjury.
Finally, a man who headed the Elan School in Poland Spring, Maine, during the nearly two years that Michael Skakel attended the private institution and received treatment for emotional and behavioral trouble has been ordered to appear after initially refusing. Michael Skakel reportedly began living at the school in the spring of 1978, when Joseph Ricci was director.
''I can only say that Joseph Ricci was here, and that he refused to answer questions, and that he was served with an order compelling him to return on Oct. 8,'' said State Inspector Frank Garr.
In a rare proceeding, Connecticut prosecutors are presenting evidence to a single grand juror in Superior Court - Judge George Thim. About two-thirds of the men and women on the witness list have appeared, 35 in all, according to Garr, who would not comment on the content of the secret proceedings. Investigators requested the grand jury this year, saying they had new evidence in the case.
Yesterday, Dorthy Moxley said she has always wanted police to question Terrien, the Skakels' cousin, who also uses the name James Dowdle, and whose last known address was reported to be on Nantucket.
''On the night that Martha was missing, I called the Skakels many times, and one time Julie [Skakel] suggested I call the Terriens, and when I called, he [James] wasn't home,'' said Moxley.
A source familiar with the investigation said an attorney for the Skakel family is fighting the introduction of material in a private investigator's report, detailing how Michael and Thomas Skakel apparently changed their accounts of the night of Halloween Eve, 1975.