Ana Walshe’s paramour William Fastow took the witness stand Thursday in the murder trial of her husband, Brian Walshe, testifying that the two began an “intimate” relationship before she vanished without a trace on Jan. 1, 2023.

Fastow, a realtor, helped her find housing in Washington, D.C., where she was commuting to work from her family home in Boston.

Fastow, like Ana, had children, although he was separated from his own wife, he testified.

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They became close, bonding over common interests, including in fitness and over the struggles they had in common as parents. Then they began their affair, he said.

Although he never stayed at her Washington townhouse overnight, she stayed at his, he said. He said he did not keep the affair a secret generally, but that Ana had told him that if her husband ever found out, she wanted him to find out from her.

Still, the two went on a trip to Dublin, Ireland, for Thanksgiving in the months before her murder. After Dublin, Ana flew to Serbia to visit her mother, while he returned to Washington. They also spent Christmas Eve together in Washington, he said, allegedly infuriating her husband when her flight was delayed. She drove from Washington to Cohasset.

She had also set up rooms for her three children in her townhouse, he said, anticipating that they would be moving in there.  

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“Ana was extremely disappointed that she wasn’t in a position to be the mother she believed the children deserved,” Fastow testified.

He testified that Ana told him that her children lived with their father in Cohasset, a suburb of Boston, because Walshe’s home confinement for a federal art fraud conviction was contingent on him being their primary caretaker.

Prosecutors have alleged two potential motives in the slaying. The first is anger over the affair. The second is because he allegedly believed he would have a better chance of avoiding federal prison if his wife were out of the picture, and he was the only caretaker for their three children.

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Walshe’s defense has denied that he had any knowledge of the affair, although he mentioned Fastow more than once during interviews with detectives before his arrest and allegedly looked him up on the internet before Ana’s disappearance.

Her remains have not been found, but prosecutors showed the jury Wednesday a saw and hatchet recovered from a dumpster near Walshe’s mother’s house that the defendant allegedly used to dismember his wife. The same dumpster also had her COVID-19 vaccination card, clothes, bloody towels and a cut-up rug suspiciously similar to one taken from the family home.