A Queens man who slashed the throats of his wife and 14-year-old son — and blamed it on an alter ego named Roberto — ghoulishly summoned his mistress to check out his bloody handiwork, according to law-enforcement sources.

“I want to show you my family,” Otto Herrarte, 48, told Giovanna Fernandez before leading the horrified woman to the closet in his Corona apartment where he had wrapped the bodies in black plastic, the sources said.

Police say he butchered Edna Herrarte, 52, and their son Daniel on Friday morning while another son, David, 15, was at school.

He then hid the crime for 24 hours, telling David that his mom and brother had been in a car accident.

Sources said Herrarte asked Fernandez to help drive David to his uncle’s in Jamaica, then took her to his home and revealed his grisly surprise. She called 911.

Herrarte last night made a brief court appearance,, where he was remanded for psychiatric evaluation.

Prosecutors said he told cops, “I am both Otto and Robert.”

He also claimed he did not kill his wife, blaming his alter ego, but said, “I cleaned the knife went to the store and bought duct tape and black bags. I cleaned up after him.”