Merrin is a native of the planet Orban and was the people's expert in naquadah reactors. She was introduced in the episode, 3.05 "Learning Curve".
It came as a complete surprise to Jack and Carter that Merrin, an eleven-year-old Orbanian, was her world's expert on building naquadah reactors. She went with her adult escort, Kalan, to the SGC as part of an exchange program SG-1 had arranged with the Orbanians, who were technologically advanced. Merrin was an Urrone, a child specially selected to carry on the knowledge of her predecessors through the use of nanotechnology. When she reached twelve years of age, the nanites would be removed and distributed to the other Orbanians in a ceremony called the Averium. Unfortunately, this ceremony would remove all of her knowledge and leave a shell of a person because the nanites were placed in her at infancy, before the her neuro pathways were developed.
She stayed with Carter to show her how to build a naquadah reactor. Carter enjoyed the process of learning new things and trying to figure things out for herself. Merrin could not undertand this. Instead, she was wanting to tell Carter how the reactor worked. Carter showed her how to draw and Merrin drew detailed schematics of the reactor. Jack saw how attached to the technology Merrin was and felt that she needed to take a break and have some fun, but this idea was totally foreign to her.
Daniel and Teal'c discovered that once the nanites were removed, the Urrone was left without memories and was basically reduced to near-infancy. Their hearts were broken when they saw Tomin, one of the Urrone they had spent much time with, after his Averium. Tomin decided to go to the Averium before he turned twelve because he felt that the information he obtained from Daniel and Teal'c about the Goa'uld was too important for his people's survival to wait. When Kalan explained the role of the Urrone to Daniel, he understood the importance of the child's role, but was disturbed by it. Once Jack learned that this fate was what awaited Merrin, he decided to act. He took her to one of the schools which Cassandra Fraiser had attended to show her how children her age played and learned on Earth. Merrin learned children's games, such as hopscotch, and how to paint pictures of things she liked (but Jack required that it not be a piece of technology).
After their time at the school, Jack returned Merrin to the SGC and gave her a box of crayons as a good-bye gift. Merrin went through the Averium, but something happened that the Orbanians did not expect: she passed on the experiences of having fun to those who received her nanites and they, in turn, taught some of the former Urrones the same. Merrin's legacy to her people created a bridge between the cultures of Earth and Orban and gave hope that the former Urrones could once again live vital lives.
--DeeKayP 18:22, 21 Apr 2005 (PDT)