A brother and sister fatally stabbed to death in their Upper West Side apartment were laid to rest a private memorial service earlier this week at Avery Fisher Hall in Manhattan. 

The bodies of Lucia Krim, 6, and her 2-year-old brother Leo were found by their mother, Marina Krim, in the bathtub of their apartment the night of October 25, according to authorities.

The children’s nanny, 50-year-old Yoselyn Ortega, was found unconscious and bleeding from what police believe were self-inflicted knife wounds, CNN reported. The family’s other child, 3-year-old Nessie, was out of the apartment with her mother at the time of the deaths.

CNN reported that on Saturday afternoon, Ortega was interviewed at the hospital where she remains under guard. Ortega was arrested and charged with first- and second-degree murder in each of the stabbing deaths, New York police spokesman Paul Brown said.

Grieving father Kevin Krim spoke at the memorial service where he recalled happier times the family shared, The New York Daily News reported. However, Krim reportedly broke down in tears when he said his two children were gone because of a “meaningless, violent crime.”

The Krims released a statement on their Tumblr site the day of the memorial, thanking everyone for their “extraordinary outpouring of love and kindness.”

“Lulu and Leo were 2 of our 3 best friends, and we miss them so much. Our daughter Nessie is very strong, and with your support we will be strong for her. Today we gathered family and friends to celebrate the beautiful lives of Lulu and Leo. It is important to us that they are remembered as the sweet, creative, and fun-loving children that they were,” the parents wrote in the statement.

“We are honoring our children by creating the Lulu & Leo Fund. The fund will support participatory art and science education for young children in schools, museums, and other community institutions. Lulu’s art classes provided some of her most joyful and enriching moments. We’d like to help other children obtain access to similarly great experiences,” they said.

The distraught parents also asked for support in ensuring that their only surviving child, Nessie, is afforded the opportunity to grow up privately.

More information about the Lulu & Leo Fund can be found here.

It was unclear whether Ortega has obtained an attorney at this point.