The now 88-year-old Rose-Marie Silbermann-Frenkel wants to get a precious painting that she donated in 2013 back to the Rijksmuseum,
The family has now seized the artwork.
It concerns a painting from 1918 by the Utrecht painter and designer Bart van der Leck, which is now worth around 350,000 euros.
Silbermann-Frenkel says that she donated the painting in a confused state and that at the time of the donation she was incapacitated.
Her seventeen-year-old granddaughter had a brain tumor.
Voices in Silbermann-Frenkel's head told her to give the painting as a sacrifice so that her granddaughter could survive.
The family says the museum has failed to comply with its duty to investigate.
The current director Taco Dibbits has
in a response
that the museum has acted "in good faith".
If the judge rules otherwise, he will return the painting.