Q. Where can I find some database articles about success in family-owned businesses?

You can find articles on this subject in the COM Library academic databases.  Follow the link below to the databases guide.  Click on "P" and select ProQuest Central.  In this database, search for "family owned business" AND "success rate".  Use the quotes and the capitalized AND.  This will tell the database to find articles that have those terms together and not look for just the separate words.  You should be able to find articles you can use from the resulting list.

You can also do a similar search in any of the other databases that target business subjects.  I have that link below for you.