Looking for information/references re: impact of attachment disruption on young children

["Kavanaugh, Amy" <akavanaugh@xxxxxxxxxxxxxxxxx>]

I am currently doing a bonding evaluation with a nearly four year-old child
who has been raised by the same foster mother since infancy.  An extended
family member is requesting custody of the child.  Does anyone know of any
research related to the impact of returning children/moving children from
one caretaker to another after being raised in one place for a protracted
period (e.g. the impact on young children of disrupting a healthy
relationship)?  I would appreciate any leads, suggestions, or references
folks might be aware of.

Thank you.

Amy L. Kavanaugh