There are never stupid questions - only stupid answers.
More detail is needed to be helpful for your answer. Yes, there are ways it can be done - depending on the application, practicality and expense.
What is it that you are trying to power with 12V? what is the current (amps) that will flow?
What are the specs of the 9V source? current potential equals ?
Are you looking to integrate the modification directly into circuitly of your device? Will you accept an external add - on?
Must the unit be portable when you finish?
just a few questions to clarify what you are attempting, I'm others will ask similar questions or for more details.
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