The second is wrong.
Interested in Language
This is a title and I'd like to know which one is better English, I'm sure 1 + 3 are fine, but 2 seems wrong.
1. The Retirement Savings you didn't know you had.
2. The Retirement Savings your didn't know you have.
3. The Retirement Savings you don't know you have.
rerlou, please note that a better title would have been The retirement savings.
(I don't see a reason to capitalise 'retirement savings'.)
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