So the most convenient way to sway children to relocate is via the dome policy. Only in case a Shuttle Hub is available can they be manually ordered to relocate to an unconnected dome.

Children will prefer living in a nursery in the same dome they currently reside in and will not relocate to a directly connected dome even if it contains a nursery with an available spot. When a colonist is born they are immediately considered a child (cf. Upon landing on Mars, colonists will try to find a residential building within walking distance to live in. But the intended way to properly manage the colony is via setting the dome policy per dome, the specialization policy per building, via training the needed specialists at the Martian University, and of course via getting only the right applicants from Earth. The player can manually re-assign the housing as well as the work place of each an every individual colonist. The player cannot micromanage them, but only provide for the necessary facilities: a place to live in, a place to work at, and places to fulfill their interests.

Colony survival game death