You cannot claim them as dependents if they lived with you for "half the year." You do not need permission to claim a dependent that you can actually legitimately claim. But your roommate/friend and her child are not related to you. Unless they lived with you for the entire year, and your friend had less than $4700 of income, she cannot be claimed as your dependent, nor can you claim her child as your dependent.
Not sure what information you saw that led you to believe you could claim them, but you cannot. And if you claim them when you should not, you would face repayment of any tax credits you received for claiming them as well as penalties. If you are paying for 100% of their support and do not want to continue doing so, then perhaps they need different living arrangements.
IRS interview to help determine who can be claimed:
https://www.irs.gov/help/ita/who-can-i-claim-as-a-dependent
WHO CAN I CLAIM AS A DEPENDENT?
You can claim a child, relative, friend, or fiancé (etc.) as a dependent on your 2023 taxes as long as they meet the following requirements:
Qualifying child
- They're related to you.
- 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're under the age of 19 (or 24 for full-time students).
- No age limit for permanently and totally disabled children.
- They lived with you for more than half the year (exceptions apply).
- 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 $4,700 in 2023.
- 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:
