Hi LMC1240,
Thank you for your interesting question! Both VT and PA have the same general rule for residency; that you are a "resident" if you spend more than 183 days in the state. Therefore, it is possible you could be residents of different states and nonresidents of different states and file state tax returns accordingly.
You did not mention your income situation, whether you are working, retired, etc. If you are working and have wages, they will generally be taxed where they are earned or where you are working. The taxation of retirement income varies from state to state and you would need to look at the specifics according to the type of retirement income and the state's tax treatment.
Hope that at least covers the basics of a complicated question!
