Kim Zolciak to Judge -- My Mom is an Unfit Grandparent

Kim Zolciak's two young daughters have sworn under oath ... they DO NOT want to be forced to spend time with their grandmother ... claiming she's nothing but a disrespectful old lady.

The kids are responding to a lawsuit filed by Kim's mom Karen Zolciak -- who wanted the court to FORCE Kim to let her spend time with her granddaughters.

In her docs, Karen had claimed Kim cut her off from the kids back in 2011 ... simply because she used an off-limits indoor bathroom instead of a porta-potty at Kim's televised wedding to NFL player Kroy Biermann.

Now, Kim's kids -- Ariana and Brielle Zolciak (ages 11 & 15) -- have submitted sworn affidavits to the court ... in which they beg the judge to shut Grandma down, explaining, "We both love our grandparents, but due to their actions at the wedding of [Kim and Kroy] ... we have grown apart."

The girls say they have no real desire to see their grandparents ... and insist they have too much going on in their lives to be forced to hang with Granny for overnight visitations.

In the docs, the girls also fire back at Grandma's claims that Kim pushes them into the spotlight -- saying, "We do not live a crazy or abnormal life. We are not forced to appear on television with our mother."

The girls -- and Kim -- are asking the judge to throw out Karen's case. Kim also wants her mom to pay for her legal costs.

Gonna be a fun Thanksgiving.