Your newly divorced friend does not need to enter anything whatsoever about her ex-spouse's income on her own tax return. She is now either Single ( or perhaps Head of Household if she is the custodial parent of the children.) Nothing about her ex-spouse goes on her return with a filing status of Single or Head of Household.
If she had no income in 2020 then she has no income to enter on a tax return. She will not be eligible for any child-related tax credits if she did not earn any income on her own. If there is a signed form 8332, the "ex" spouse can still get the child tax credit for a dependent child under the age of 17, but no other child-related tax credits like earned income credit or childcare credit.
You do not say whether your friend received stimulus checks #1 or #2 while still married -- so we cannot comment on whether she should be using the 2020 recovery rebate credit to get any of that stimulus money.
**Disclaimer: Every effort has been made to offer the most correct information possible. The poster disclaims any legal responsibility for the accuracy of the information that is contained in this post.**
