Accused “killer nanny” Yoselyn Ortega is not the catatonic “parakeet” she appears to be — and is mentally fit to stand trial for the slaying of two children in their Manhattan apartment, a judge ruled yesterday.

State Supreme Court Justice Gregory Carro found “clear and convincing evidence” of Ortega’s fitness after eight days of conflicting testimony by psychiatric experts.

Prosecutor Stuart Silberg told Carro that Ortega was able to conduct coherent phone conversations with relatives from Rikers Island.

That contrasted with her stolid appearances since she was arrested Oct. 25 for the brutal slaying of Leo Krim, 2, and Lulu Krim, 6.

“She’s simply not being honest about it,” he said.

Ortega’s lawyer, Valerie Van Leer-Greenberg, said her client can’t remember the killings — or her own suicide attempt afterward.

“The defendant is tantamount to a parakeet,” she said.