If all three kids (1) lived with her for over half of the year, (2) are full time students under age 24 and (3) did not provide over half of their own support"

• All three kids should be on her tax return for EIC purposes (look at Schedule EIC to see if all three kids are showing up there).
• If she did not let the father claim the one kid, all three kids would also be dependents (look at the dependent section of Form 1040 to verify they are showing up there).

If you tell us (1) her earned income for 2022, (2) her AGI for 2022, (3) her earned income for 2023 and (4) her AGI for 2023, we may be able to point you to why her credits have changed so much.