Updated

A Canadian woman nicknamed the "Black Widow" for her ability to persuade grieving widowers to marry her pleaded guilty on Monday to drugging a man she married days earlier.

Melissa Ann Shepard, 78, was charged last October after her latest husband, Fred Weeks, fell ill at a bed and breakfast in Nova Scotia four days after they married. She pleaded guilty to administering a noxious substance and failing to provide the necessities of life.  Prosecutor Gerald MacDonald said outside court that an attempted murder charge was dropped because the prosecution couldn't prove that Shepard intended to kill Weeks.

Shepard became known as the "Black Widow" because of her prior convictions stemming from her past relationships. She was convicted of manslaughter in 1992 in the death of her second husband, Gordon Stewart, who she drugged and run over twice with a car.  In 2005, Shepard -- who has gone by several other surnames -- was sentenced to five years in prison on seven counts of theft from a man in Florida who she had met online. Alex Strategos, now 81, said she stole $20,000 from him over the month that they lived together.

In the latest case, the prosecution read an agreed statement of facts in court, saying Shepard mixed in the tranquilizers Lorazepam and Temazepam into Weeks' drinks while they were aboard a ferry from Cape Breton, Nova Scotia on their way to Port-aux-Basques, Newfoundland for their honeymoon. A ferry employee told investigators that when Weeks came aboard the ferry bound for Newfoundland, he was spry enough to easily walk 200 meters (220 yards) from his car to an elevator and was cracking jokes when he and Shepard were escorted to their cabin on Sept. 26.

But Weeks was "a totally different person" the next day, the employee said, adding that Weeks was unable to walk, couldn't put on his sneakers, didn't know where his car keys were and required the use of a wheelchair.

The couple briefly stayed in a Newfoundland hotel but checked out that same day before returning to North Sydney, where they stayed at a bed and breakfast. It was there he fell out of bed and was hospitalized, the statement said.  At the hospital, Shepard misinformed nurses and doctors about his health, saying he had prostate problems, bowel surgery and was suffering from dementia and chronic obstructive pulmonary disorder, the court heard. She also told hospital officials that Weeks, a father of six adult children, had no other family.

Shepard is to return to court Tuesday morning for a sentencing hearing. She faces a maximum sentence of two years for the charge of administering a noxious thing and 18 months for failing to provide the necessities of life.

She married Weeks in a civil ceremony on Sept. 25, a few weeks after they met. But their marriage was later declared invalid by the province's Vital Statistics Division after it said false information was provided on the marriage certificate.