The voices of the St Mary's Cathedral choir soared but the mood was sombre on Sunday as a prayer was offered "for those who have died in tragic circumstances".

To the left of the altar sat a small white board adorned with pink flowers and bearing photographs of Maria Claudia Lutz and her smiling children, Martin and Elisa.

Social worker Isabella Almendrades with the tribute in St Mary's Cathedral. Credit:Michele Mossop

The tribute to the 43-year old mother, who was found dead in her Davidson home along with her young children and husband, Fernando Manrique, was placed there by Sydney social worker Isabella Almendrades.

Ms Almendrades, from Brighton-Le-Sands, met Mrs Lutz and her husband when they moved to Sydney from Colombia a decade ago.