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My scout is now registered in two units (a Ship and a Troop).
When I log in as a parent and click on him under My Family, I have an option to see his Troop membership and advancement, or his Ship membership and advancement.
When he logs into Scoutbook, he only sees the membership and advancement information for his Troop.
The same thing happens at advancements.scouting.org - he only sees his troop, but when I log in there I see him in both of his units.
@MT01 OK I found that one - the scout is NOT registered officially in a Ship. The scout Might not see it as it is not official or approved, not sure on that would have to test it.
That means nothing to be in Scoutbook - the scout needs to apply to be in the ship and be accepted - either at beascout.scouting.com - or if you switch your primary to 133541150 you might be able to use My Applications to register him (but I bet not as it is a different council) - or fill out a paper app