The development of MORS-Child is described in the following research document:
Simkiss, D.E., MacCallum, F., Fan, E.E.Y., Kimani, P.K., Oates, J.M. and Stewart-Brown, S. (2013) ‘Validation of the Mothers Object Relations Scales in 2-4 year old children and comparison with the Child-Parent Relationship Scale’, Health and Quality of Life Outcomes, vol. 11.
The quality of the parent–child relationship has an important effect on a wide range of child outcomes. The evaluation of interventions to promote healthy parenting and family relationships is dependent on outcome measures which can quantify the quality of parent–child relationships. Between the Mothers’ Object Relations – Short Form (MORS-SF) scale for babies and the Child–parent Relationship Scale (C-PRS) there is an age gap where no validated scales are available. We report the development and testing of an adaptation of the MORS-SF; the MORS (Child) scale and its use in children from the age of 2 years to 4 years. This scale aims to capture the nature of the parent–child relationship in a form which is short enough to be used in population surveys and intervention evaluations.
You can access the paper here: http://oro.open.ac.uk/id/eprint/37587