W-4 Married Filing Jointly

I am starting a new job and need to complete a new W-4. I plan to select "Married filing jointly" and then use option 2b in step 2. We have 1 dependent to claim and I am the higher earner, with my wife earning less than 50% of my income. I understand that my form should include the extra withholding amount (4c) based on the worksheet as well as the $2,000 credit for 1 dependent, but how should my wife update her W-4? Should she also have the same extra withholding amount? What should her W-4 look like?

 

Thanks in advance!