[2] Between 1902 and 1908 she taught children in a secular environment but in November 1908 decided, along with her sister, to enter a convent of the Ursulines near Ahrweiler.

[1][2] Merten led a simple life with an emphasis on tending to the children entrusted to her while also associating action and contemplation with the huge devotion she fostered towards the Eucharist.

Merten died in mid-1918 at the convent of Saint Bantus due to her tuberculosis and she was buried at the Basilica of St Paulinus in Trier.

A medical board approved the healing to be a miracle on 25 June 1986 as did theologians on 19 December 1986 and the Congregation on 17 March 1987.

John Paul II approved it on 8 May 1987 and beatified Sr. Blandine in Saint Peter's Square on 1 November 1987.