A co-owner is suing after the defendant fraudulently partitioned property, misrepresenting occupants and obtaining an ex-parte order by serving notices to deceased individuals. The defendant now claims ownership via an old deed, contradicting their earlier claim of co-ownership and partition. The question is whether the defendant is now estopped from denying the partition, and if this argument can be raised without amending the initial civil suit, which is currently at the cross-examination stage.