Non-refundatable tax credits "Other amounts" for my wife doesn't make sense

Let me specify some background info to help you understand:

- Me and my wife are married and filing jointly in Turbotax Premier website

- Me and my wife are not separated, basically just a couple living together

- We have two young school-aged children, both younger than 14

- None of us is claiming any disability

- Me & my wife are not students currently or in any past filings. Didn't claim any tuition, school related credits ever.

- In the filings my income is around 65k, and wife's is around 28k. Other than the BPA, we don't have other credits 

 

But somehow in Turbotax, a large non-refundable tax credits is auto generated in my wife's filing. I couldn't figure out why. I even re-did everything from scratch, same amount still shows up. This makes her no need to pay any tax, but it's not some credit I expected so I'm worried if I file like this, there would be an issue later on.

 

In "Bottom Line (tax summaries)" > Detailed Tax Summary, that "Other amounts" in her filing shows:

Taxable income
26000 Taxable income 28,770.88

Federal non-refundable tax credits
30000 Basic personal amount 15,000.00
32300 Your tuition, education, and textbook amounts 13,770.88
33500 Total 28,770.88
33800 Total @ 15% 4,315.63
35000 Total federal non-refundable tax credits 4,315.63

 

Hope someone can shed some light on this.