Dual packs

[Jmdean3]

I'm wondering what the national policy is on having a cub scout belong to two different packs. I've seen some answers that this is allowed, one is designated the primary unit and is responsible for advancements and such....can anyone link me to or copy the section from the National policy that addresses this?
I'm a first time scouting mom and trying to get my bearings. Thanks!

[FieldSports]

From Guide To Advancement:

Dual Registration. If a Scout has multiple registrations
with units in different councils, his advancement records
should be maintained in only one of the units. As he
passes requirements in any other unit, the information
should be relayed to his primary unit so only one
advancement record is maintained. It is not possible to
electronically consolidate data across different units in
different councils. If advancement records are maintained
in multiple units, then cooperation between the units will
be required in order to generate the reports necessary to
report and obtain the awards. Pg. 42