People.com said Preston, 2, and Jayden, 1, were driven to Spears's home Monday by a bodyguard for her ex-husband Kevin Federline. The children were also allowed to visit Spears Saturday.
Los Angeles Court Commissioner Scott Gordon last week agreed to let Spears see her children as long as it was in a therapeutic setting.
Media reports said the singer's father and psychiatrist are required to be present during the visits.
Federline is believed to have supported the decision to allow Spears to see their boys again.
Before Saturday, Spears hadn't seen her children in more than a month.
She was hospitalized for psychiatric treatment twice in January and was stripped of her visitation rights after she refused to return the children to their father at the end of a supervised visit last month.
Federline has since had sole temporary physical and legal custody of the boys.