The FBI investigators told her there was nothing wrong with that, they just wanted everyone to be safe, she said.
The Tsarnaevs and Misha
A friend named Misha, whom Tamerlan met in the United States, steered the older suspect toward a more devout practice of Islam, Tamerlan's relatives have said.
"Tamerlan was close friends with him, so they think that Misha made him ... become more deeply religious," Zubeidat said.
She was impressed with the Armenian convert to Islam, who seemed "very intelligent, nothing wrong." He suggested that she cover her hair with a scarf, which she did.
"When Misha visited us ... he just opened our eyes, you know ... really wide about Islam. He was really, he's devoted, and he's very good, very nice man," Zubeidat Tsarnaev said.
Tamerlan's uncle Ruslan Tsarni had a less favorable opinion.
"This person just took his brain," he said. "He just brainwashed him completely."
Tamerlan, a former Golden Gloves boxer, left the ring and stopped listening to music under Misha's influence.
Elmirza Khozhgov, a former brother-in-law of the brothers, said the elder Tsarnaev brother introduced him to a man named Misha, but "I didn't witness him making him radical."
Zubeidat declined to be drawn on which mosques her son frequented, saying he went to any mosque he could go to. Media reports have focused on the Kotrova mosque in Makhachkala.
And she vehemently denied reports that Tamerlan had sent her text messages talking about the radical nature of his faith and that he was ready to die for Islam.
But, she said, he was always in her thoughts.
"I remember him always, always from the first day that he was born, there was no day that I don't remember him. ... He was the most caring son," she said.