The mother described an extremely close family, but admitted that her embrace of Islam in recent years was a source of tension with her husband. A few years ago, at his insistence, the couple divorced in the United States.
She said her efforts to convince Tamerlan to give up boxing on religious grounds had strained her relationship with her husband, himself a former boxer, who wanted him to continue.
After the father moved to Dagestan last year as his health failed, the mother followed a few months later, saying she was homesick. The two reconciled, deciding they couldn't live without each other, she said. The grief from losing their sons, she said, has brought them even closer together.
Tamerlan, who lived here in Dagestan, a restive region in southern Russia that is home to an Islamist uprising, with his family for a few months when he was younger, returned for a visit for the first time in February last year. He stayed until July.
His mother said he entered Russia on his Kyrgyz passport (he holds an American green card) and applied for a Russian passport while he was here.
She said Tamerlan visited family and traveled neighboring Chechnya, also home to Islamic militants, with his father to visit relatives. She denied that he met with any militants or extremists during the visit, pointing to a statement from a regional militant group on Sunday saying they had no role in the Boston Marathon attacks.