If she is has a balance due, no matter how small, it is recommended that she file an Indiana return. This will prevent her from getting unnecessary correspondence from the state that will consume her time.
As a note, below are the Indiana filing requirements:
Residents
Individuals must file if gross income is greater than total Indiana exemptions. Indiana allows the following exemptions.
• $1,000 per individual for the taxpayer (and/or spouse).
• $1,000 per qualifying dependent. Additional exemptions are available but not included in determining the filing requirements.