If all members of the family have names like Obj1, Obj2, Obj3... then you can create them by name:
For "n" from 1 to 10 : Create "Obj"&loopindex
Another workaround is to manually create a hierarchy with all family objects on an unused layout. Then you can spawn this entire hierarchy in runtime, which will create all objects at once.
do you have an example capx of how to do that?