There is no way to combine two married filing separately returns into a married filing jointly return. If you have not filed either of them yet, you can start with the return with the name you want listed first on your joint return and add the information to it from the other separate return. After entering the name of the other spouse, change the filing status to Married Filing Jointly.
If you have already filed either or both separate returns, you will have to amend one of the returns to add the other spouse and change it to Married Filing Jointly.
