Posted By Hieronymus at 4:55 PM - Fri May 25 2018
You can spark into any NPC family, although not necessarily any NPC. Some of your options will depend on the amount of Story Points you have at the time of selection. For PC families, you will have to have a family/child code to spark into a member of that family.
Some information on the subject you may be interested in that explains the selection process:
Families & Family Selection
Sense of Identity - Character Creation
Just to point out the bolded part is incorrect. You may need a code to spark into a PC family.
When you create a child you're given three options of what to do with the new NPC. The options are:
...
# 2. Open it up to the public. If you're looking to grow your family quickly and don't have enough people to do so this may be the best option. After the child reaches age 15 other players will be able to find your child in the Family Selection Screen. Due to the way inheritance works, this option will likely be more commonly used for 2nd and 3rd children. And remember, they’ll only find your child if their search query matches the constraints you've placed on players you want in your family.
Source