Seven-year-old Allison was furious. She wanted the new bicycle she saw in the store window — and she wanted it now. When her mother told her that wasn’t possible, Allison scrunched her face into a frown, looked daggers at her mother, and said, “My real mom would buy that bike for me.”

Welcome to the world of fantasy parents. Most children, adopted or not, go through this phase. They have gone beyond seeing their parents as all-powerful and all-knowing. Suddenly Mom and Dad are human, flawed, not as pretty, or as young, or as rich as somebody else’s parents.

In an attempt to rationalize such imperfections, many children invent a “family romance,” writes Dr. Elinor B. Rosenberg, in The Adoption Life Cycle. They fantasize that they are not, in fact, the offspring of these less-than-perfect people. Instead, they were born to noble parents — a prince and princess who were good and perfect and kind.

For an adopted child — who, at this age, comes to understand more fully that he or she was born to one set of parents and is being raised by another — the fantasy becomes more intense. And more complicated.

Some children, like Allison, conjure a fantasy parent when they are mad at the parents they have. Their “real” mom would be perfect, never asking them to clean their room or set the table.

But some adopted children find it impossible to conjure a reassuring image, says Dr. Rosenberg. If a child has been told her mother was “too young” or “too poor” to care for her, or that she “wanted you to have a better life,” she can’t imagine that such a parent could come and rescue her.

Fantasies of adopted children often revolve around responsibility and blame. A seven- or eight-year-old might imagine, “I must have been a bad baby, so that’s why she gave me away.” Or, “she went to parties all the time and didn’t take care of me.”

Rather than seeing himself as a “bad baby,” a child might allay such feelings by deciding that his adoptive parents stole him from his birth mother. Or he might think that since his mother was bad, he must be bad, too. Such thoughts can lead to testing his adoptive parents’ love by misbehaving and acting out.

Sometimes a child will share his fantasies — or fears — of the “other parent.” The best response to this, says Dr. Rosenberg, is to listen and reassure. “Sally, when I was a little girl and mad at my mom, I used to dream that my real mother was a ballerina. Do you ever think things like that?” An invitation to share the fantasy can open the door onto a child’s private world.