Amy, you may already know this, but on each profile is a link to send a private message. It is in the first line of the orange box. You can also post a public message in the big box on the right under Collaboration. This will be sent to the Profile Manager as well.
What you are asking to do is precisely what WikiTree is about. Collaboration. What Deborah suggests is appropriate. If you have information to add, go ahead an add it. Changes are tracked and most mistakes can be corrected.
As a courtesy, we ask you reach out to the Profile Manager and discuss what you want to do, but most profiles are made open for adding information.
Reaching out will hopefully connect you to a cousin and further the Collaboration. You may be invited to become a Profile Manager as well or put on the Trusted List if the profile is closed.
Have fun and let us know how it works out.
