The Los Angeles County Department of Children and Family Services (DCFS) has accused the pop star of being an unsuitable mother after reports of her erratic behaviour were filed.
According to reports, Los Angeles Superior Court took up an unscheduled court hearing on August 2, reports the TMZ.
Though the singer was absent during the hearing, her lawyer Dennis Wasser and Federline's counsel Mark Kaplan attended the proceedings.
The hearing raised issue about Sean Preston and Jayden James' dental hygiene, and poor eating and sleeping habits, and does not involve physical mistreatment of her children.
Reports also said that K-fed might have himself filed complaints over Spears' parenting skills, according to the Daily Mail.
The mum of two has been repeatedly charged of being irresponsible.
Recently she is said to have spent the whole night with magician Criss Angel drinking Dom Perignon champagne.
The next hearing for the custody case has been scheduled for September 4.