Real Housewives of New York City  RAMONA SINGER helps catch bad nanny after Park Avenue pal was suddenly missing a fortune in jewelry.

WHEN Ramona’s pal, Lucia Hwong Gordon Gordon, a composer, had  quizzed her live-in nanny Raquel Santos about the theft, the nanny wept, admitting she had swiped and pawned the jewels and other items including a diamond-and-ruby necklace, RadarOnline noted.

While she was hesitant to turn Santos into authorities, it was Singer who encouraged her distraught pal to do so, a source told the NY Post.

“Ramona said she needed to speak up before the woman victimized another family,” the source said.

Ramona told Gordon to bait Santos by offering to buy back the stolen goods, and when Santos showed up at her apartment to do just that, the cops were there to put her in cuffs.

The Bravo star told the NY tab, “I’m thrilled justice was served. My friend showed strength and perseverance.

“It was important that this was investigated.

“If it had not been investigated, she might have just gone to work for another family and done the same thing.”