You will have to amend your return. All income is suppose to be included in your original return. The IRS gets copies of all W-2’s, they may send you a letter asking for the missing w2. You should wait until your original return has been fully processed before you amend.
If you original returns get processed without the additional W2, you need to amend your return to add the missing W2. If your Federal amended return affects your State, you will need to also amend your State return.
https://ttlc.intuit.com/turbotax-support/en-us/help-article/tax-return/amend-change-correct-return-a...
