A memorial gathering was held at the public cemetery in Maarn 50 years after Melissa van de Waerdt and her father Jan found the remains of an unidentified girl near the A12 towards Arnhem. The girl, known as the Heulmeisje, remains buried in an unnamed grave and her identity is still unknown.

A memorial stone was unveiled during the gathering, which was intended to commemorate the girl and keep the search for her identity alive.