'American Idol' Caleb Flynn's Kids Seek Restraining Order to Protect Assets After Mom's Killing

A lawyer for "American Idol" alum Caleb Flynn’s two daughters is asking a judge for a restraining order against the singer, in order to preserve their financial security ... TMZ has learned.

The kids' guardian made the move as Caleb remains locked up on a murder charge over the death of his wife -- the kids' mother, Ashley Flynn. According to the papers, the restraining order should prevent Caleb from transferring any assets ... including money that may have been left behind by Ashley.

The filing claims the children face immediate and irreparable harm if Caleb starts selling off assets ... including the home they live in, cars owned by the family, and bank and retirement accounts.

As TMZ first reported, Caleb was seen crying on bodycam footage when officers arrived at his Ohio home to find Ashley dead on February 16.

Caleb told dispatch that his wife was shot by a burglar. Authorities found Ashley in the couple’s bedroom, with their kids asleep in a room nearby.