The work of integration for your foster/adopt child involves the integration of past, present and future into a cohesive timeline narrative, with an integration of what I call, 'the good', 'the bad' and 'the ugly' of the past events before they were adopted or placed in fostercare.
This is not to say that all adoptees have the same paths to developing into healthy adults or the same intensity of traumatic events in their past to process. Some adoptees can move fairly fluidly around the present time boulders in the stream of life, if they have established a secure attachment with their adoptive parent/parents. In my experience of working with adoptees over the years I have heard and witnessed many different life journeys.
However, all adoptees have the same irreplaceable loss to try to understand and negotiate. The loss of Birth mother and Birth father and possibly siblings and possibly Birth family ancestory. Along with this loss comes the question "why was I adopted? No matter how much an adoptive parent rationalizes,or denies, or sugar-coats or simplifies or tells the truth each time it is asked - this question does not go away, nor does the loss for an adoptee. Embracing all of your adopted child, the good , the bad , and the ugly- the joys and the saddness- will not answer the question or take away the loss; but it will give a secure foundation from which your child can find her own answers over the life span. That is the best we can do as adoptive parents.