TMZ video of Kevin in his black Navigator.
Britney Spears got an early morning visit from her family on Wednesday.
Estranged husband Kevin Federline, 28, brought his sons Sean, 17 months, and Jayden, almost 6 months, to visit their mother at Promises Residential Treatment Center on March 7.
Federline and the children left his house in Tarzana, California, in a black Navigator (outfitted with curtains to ensure privacy) at 5:30 a.m., arriving at Promises at 6 a.m.
"It seems like Britney is struggling being away from Sean P. and Jayden because Kevin let her spend four hours with the kids," a source tells Us.
The trio returned to the Tarzana house at 10:30 a.m.
The evening prior to the visit, Spears, 25, was allowed to leave the facility and spend an hour at her Malibu home five minutes away from Promises.
According to an eyewitness, a chauffeur driven van took Spears to her home while two bodyguards in separate SUV's struggled to block photographers.
The eyewitness added that the pop star was covering her face and seemed upset.