No mother should have to worry about something like this.

Britney Spears is fearful that Kevin Federline could use her two sons as leverage to get the massive increase in child support he's requesting.

"Britney is extremely agitated and extremely concerned that Kevin is going to no longer allow her to see their children because he has sole custody as retribution for not agreeing to the $40,000 in child support payment, which would be a $20,000 increase from what he is getting now,” a source told Us Weekly.

The former backup dancer has four other kids and only makes approximately $3000-a-month from DJ'ing, and he wants his payments from the pop princess tripled, but her camp is fighting back.

"Britney’s father, Jamie, had signed off on a modest increase of $25,000, but demanded a monthly accounting of how that money was being spent. Kevin has four other children from previous relationships, and it’s not Britney’s responsibility to pay for their care," the insider explained.

Brit Brit, her dad, and her lawyers can't see how $20K-a-month isn't covering the costs for Sean, 12, and Jayden, 11, seeing as how the singer is the one coughing up the dough for the big expenses.

"All of Preston and Jayden’s expenses are paid for while they are with Kevin, from schooling, clothes, insurance... There is nothing that Kevin has to pay for. Nothing has changed in the care Britney has given the kids and Kevin has acknowledged what a great mom she is … Lost in all of this is the kids, they are the ones caught in the middle," the source added.

Popozao needs to get a J-O-B!