No. 19 caught Michelle Duggar by surprise.

The 42-year-old mom of 18 noticed that she wasn't losing weight — even though she and husband Jim Bob were on Weight Watchers — and her 8-month-old baby was fussing while nursing. In the past, she found a fussy infant meant a change in breast milk that came with pregnancy. So she took a pregnancy test. "And lo and behold, I was just pleasantly surprised that this was positive," Duggar said yesterday.

The Duggars live in Tontitown, Ark., and are featured with their family on TLC's "18 Kids and Counting."

The announcement of the Duggars' 19th child comes as their oldest, 21-year-old Josh, is about to become a father himself. Married last year, Josh and wife, Anna, are expecting their first child, a girl, on Oct. 18.

The grandchild will be about five months older than her future aunt or uncle, due March 18.

JACKSON'S DEATH FILE NOTES FATAL INJECTION

Michael Jackson's death certificate has been amended to reflect his cause of death as a homicide, specifying "injection by another" as the fatal injury.

The designation was not a surprise — coroner's officials said last week that they believed Jackson's June 25 death was a homicide.

Investigators have said a mix of the powerful anesthetic propofol and another sedative killed the pop singer. The new record lists "acute propofol intoxication" as the main cause of death and "benzodiazepine effect" as another significant contributor.

Jackson is scheduled to be interred tomorrow at Forest Lawn Glendale.

The document does not mention Dr. Conrad Murray, Jackson's personal physician. He told detectives that he gave Jackson sedatives and the anesthetic propofol to help him sleep. No criminal charges have been filed.

COSBY 'IN' WITH DETROIT SCHOOLS EFFORT

Bill Cosby had heard about the tough-as-nails, uncompromising man tackling fraud and improving Detroit's public schools, and wanted to help.

So the 72-year-old actor, comedian and activist decided to loan the district his celebrity as Detroit tries to hold off plummeting enrollment amid a fiscal crisis that a few weeks ago spurred suggestions of a possible bankruptcy. Cosby said yesterday he has joined "I'm In," emergency financial manager Robert Bobb's $500,000 campaign to stop the flow of students leaving the district — and maybe persuade parents who have sent their children elsewhere to give Detroit another shot.

SPECTOR MOVING TO ANOTHER PRISON

Music legend and convicted murderer Phil Spector, who complained recently about his prison quarters but later said he wanted to stay put, is being moved to make room for inmates requiring outpatient mental health treatment, a corrections spokeswoman said yesterday.

Spector and other prisoners will be going to Pleasant Valley State Prison in Coalinga. He is serving 19 years to life for the murder of actress Lana Clarkson.