Occurs when linking records from the Link records grid
Student Current Statues filter is incorrect

1. In the Integration, click Setup Integration with The Raiser's Edge.
2. Highlight Student Relationships.
3. Under the Student Current Statuses filter, select the student status that should be considered when adding student relationships.

If after following the steps above and still the Relationships are showing to be added as Non-Constituents instead of Constituents Contact Support and reference this article.