The Crawford hybrids (played by David Lovgren and by the Casey and Sean Murphy twins as children) were a series of hybrid clones produced from female abductees' ova. They were employed by the Syndicate in the colonization project. The individual they were cloned after is unknown, but it is possible he was the son of a Syndicate member. Kurt Crawford was the name of one man in the Crawford series, but since the rest of them are not named, this name is also used as a reference to the whole group, similarly to the Gregor or Samantha Series.
Kurt Crawford
Kurt Crawford was a resident of Allentown, Pennsylvania who worked at the Lombard Research Facility, developing other alien-human hybrids like himself. He was a member of the Allentown MUFON group, where he had met and befriended the female abductees whose ova had made his existence possible as well as the many hybrids he had helped to create. This membership seems to indicate he was the first Crawford to seek answers about his origins and the first to become opposed to colonization. When agents Mulder and Scully tried to find the source of Scully's cancer, tracing it back to her abduction in 1994, the duo met Kurt Crawford who was downloading data from the computer of the late MUFON founder Betsy Hagopian, as she had requested. Kurt Crawford answered the agents' questions and later helped Mulder going through the MUFON files at Betsy Hagopian's house, although he never revealed his hybrid identity. Because of his affiliation with the MUFON group, Kurt Crawford was targeted by the Syndicate and killed that night, in February 1997.
The Crawford Scientist Hybrids
Unaware of Kurt Crawford's assassination, Agent Mulder subsequently tried to contact the man without success. He also discovered the MUFON files had disappeared and was left with the impression that Crawford was an impostor. But based upon the information he had obtained from those files, the agent continued his investigation and eventually met the rest of the group. Half a dozen of them worked at the Lombard Research Facility and it was there revealed that they were all involved in a resistance against colonization, as they meant to "subvert the project" that had created them. Mulder also learned they were attempting to save the ailing abductees. One of these hybrids showed Mulder to the vault where the abductees' ova were kept, leading him to Scully's and letting him leave with one of her vials. The laboratory where they worked included large tanks filled with a green amniotic fluid in which blond hybrid boys Mulder had previously seen were gestating; the agent understood they were younger Crawford clones and that he had met identical boys on a Syndicate plantation in Canada.
The Crawford Agrarian Drones
The Crawford series included a group of mute hybrid children stationed on a secluded farm in Alberta, Canada. These boys worked alongside young Samantha Mulder clones, taking part in an experiment with smallpox-carrying bees. The bees became carriers as they collected the infected pollen from ginseng shrubs and the Crawfords' task consisted of basic horticultural work and beekeeping. The boys' isolation from the human population made them curious when visitors approached the plantation. One such visit involved a Telus technician who was stung by a bee and died at the boys' feet; the children's apparent indifference seems to suggest they had seen many die in such a fashion.
The Crawford agrarian workers had most likely been created at the Lombard Research Facility by their older brothers.
Background information
The character Kurt Crawford was named after Chris Carter's contact at the FBI.
The scenes featuring the many Crawford clones together were achieved using motion control with lead actors and doubles.