Welcome! This forum has a treasure trove of great info – Scouters helping Scouters! Just a heads up, though - all content, information, and opinions shared on this forum are those of the author, not the BSA.
They are the same parent, attached to the same scout. One of the names has parentheses in it, which makes it impossible to add Preferred Name, Address, and Phone to the profile.
I think I’m agnostic about which ID merges into which. Thanks in advance.
I merged them in Scoutbook
136840056 is the survivor
Ask the parent to log into http://my.scouting.org and click on the menu in the upper left. Click on Manage Member ID and make sure 136840056 is there and set as primary
Then he should be able to log into Scoutbook OK