Are you familiar with the IRS resources? There is an Interactive Tax Assistant "wizard" for these scenarios.
https://www.irs.gov/help/ita
Plus:
https://www.irs.gov/credits-deductions/individuals/dependents
https://www.irs.gov/faqs/filing-requirements-status-dependents/dependents
Those are great places to start from.
*******************************
Don't yell at us; we're volunteers
