"Thanks for your concern," Kevin Krim, 37, a CNBC vice president overseeing digital content, texted to a handful of friends the day after the tragedy, in which children Lucia, 6, and Leo, were killed. "Nessie woke up this morning and is doing fine. We're obviously heartbroken."
Ortega, 50, suffering self-inflicted knife wounds, remains in a coma at New York-Presbyterian Hospital/Weill Cornell Medical Center. She is expected to be charged with the crimes once she is medically stable.
The couple's parents were traveling to New York to be with them after learning of the tragedy. The paternal grandfather of the murdered children, William Krim, said his son Kevin, now 37, met his future wife, 36, at a restaurant in Venice, Calif. The couple have been married for nine years and moved to New York from San Francisco for his work three years ago.
"I don't believe there could be a better family," William Krim, 74, told the Wall Street Journal, adding that he never heard a complaint about Ortega. "I don't understand what happened with the nanny. They gave her vacations and they were good to her, and I believe she was good with them."
Friends and family described Marina Krim, who once worked as a marketing director for a food manufacturer in Gardena, Calif., as a "hands-on mother" who only decided to hire a nanny after the birth of her third child, Leo, who just turned 2 last month.
"They're both very careful," Kevin's mother, Karen, told The New York Times. "She didn't even leave the kids that much alone with this nanny; that's the irony of all this."
A makeshift memorial to Lucia and Leo, with candles, flowers and stuffed animals, has sprung up outside the Krims' Manhattan apartment building. "It's like the whole building died," Nanny Dianne Ferguson tells PEOPLE. "Everyone's just torn up in there. I don't know what could have snapped in her mind to make her do that. It's unbelievable. "
Kevin Krim's father, William Krim, said the parents had not returned to their home. "I don't know if they ever will," he told The Times. "I don't know if I could."
Additional reporting by JANINE RAYFORD