Marina Krim doted on her three children, her neighbors often watching as she loaded them into a stroller.
She frequented nearby Central Park, close to her luxury Upper West Side apartment building on 75th Street.
Krim and her husband, Kevin, 38, were a familiar sight, with their sandy-haired children and large greyhound dog, an ex-racer named Babar.
"Very loving, always schlepping the kids with the strollers and all three climbed on the stroller together," Rima Starr, 63, a neighbor, said of Marina, 36, and Kevin Krim.
On Thursday evening, the Krims' daughter Lucia, 6, and son Leo, 2, were stabbed to death. The children's nanny is a suspect in their deaths but has not been charged, police said.
Marina Krim's grandmother, Shirley Linsley, of Banning, Calif., said she recently traveled to Rye, N.Y., for a relative's wedding, and nanny Yoselyn Ortega attended to help the Krim children during the celebration.
The children "were absolutely beautifully behaved children," and Leo had given himself the nickname "Lito," Linsley said.
"They were precious," Linsley said. "That would sum it up."
Marina teaches early childhood art at the Hippo Art Studio at the Hippo Playground at Riverside Parkhouse on 91st Street.
Parents and nannies at the neighborhood Hippo Playground sandbox fought back tears Friday as their children played dressed as Spiderman and Snow White for Halloween.
"It's devastating for us," said Hedi Urena, cradling her infant daughter. "We are a small group of families here and we feel very sad."
Marina had kept an online journal about her children, detailing their latest antics and interests, and full of happy photos, in a blog called Life with the Little Krim Kids.
The blog entries show a mother who adores her children, is charmed by their daily observations and latest tricks, and committed to sharing it all over the Internet.
In one entry, Marina Krim says that, after dropping her two older girls at school, she cherished the "3 precious hours" with little Leo.
Kevin Krim is head of digital operations for CNBC. Mark Hoffman, CNBC president, said in a statement posted on CNBC's website: "What we can do is come together to express our unwavering support for a friend."
The couple's 3-year-old daughter, Nessie, was with Marina when the slayings happened.
Kevin had been away on a business trip when the crime occurred. Police met him at the airport on his return.
With Igor Kossov
and Maria Alvarez