You cannot go back for 16 years. You can amend tax returns for up to three years back. You have not mentioned whether your MIL or SIL had any income during those years. For each of those years, there were certain amounts of income that had to be considered when determining if they could be claimed as dependents. Did they have income --not counting any Social Security? You only say they lived with you----did they work or receive any taxable income?
They might be "qualifying relative" dependents if they meet the criteria, and you could get the $500 credit for other dependents for claiming them--which is a non-refundable credit that lowers your tax due.
- They didn't provide more than half of their own support for the year.
Qualifying relative
- They don't have to be related to you (despite the name).
- They aren't claimed as a dependent by someone else.
- They're a U.S. citizen, resident alien, national, or a Canadian or Mexican resident.
- They aren’t filing a joint return with their spouse.
- They lived with you the entire year (exceptions apply).
- They made less than $5050 in 2024. (Not counting Social Security)
- You provided more than half of their financial support.
When you add someone as a dependent, we'll ask a series of questions to make sure you can claim them. There may be other tax benefits you can get when you claim a dependent.
Related Information:
INCOME LIMITS FOR QUALIFIED RELATIVE
Each year the amount changes. They have income less than
2024 $5,050
2023 $4,700
2022 $4,400
2021 $4,300
2020 $4,300
2019 $4,200
Wait until your original return has been fully processed before you amend, and make sure you have saved a pdf of the original return before you amend. (If you do not save it as a pdf, the amended return will overwrite the original, and the original will be lost forever)
See this TurboTax support FAQ for amending a tax return -
CURRENT YEAR
https://ttlc.intuit.com/turbotax-support/en-us/help-article/tax-return/amend-federal-tax-return-curr...
https://ttlc.intuit.com/turbotax-support/en-us/help-article/tax-return/amend-change-correct-return-a...
Do not expect quick results from amending. It can take four months or more for the IRS to process an amended return.
You can watch for information here:
https://www.irs.gov/Filing/Individuals/Amended-Returns-(Form-1040-X)/Wheres-My-Amended-Return-1
**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.**
