Dear Round Rock,
Based on the information provided, it appears that your sister has been found disabled and is receiving Supplemental Security Income benefits (SSI). There are several issues that can arise if she moves in with you.
1. If one of your parents has been selected as "representative payee" the checks are likely made out to that person and may even be automatically deposited into their bank account;
2. Children's SSI benefits are generally reviewed at age 18 in order to determine whether the person is qualified as disabled under the adult disability regulations, so she is likely approaching the time when the agency conducts a review of eligibility. If so, she will need to request continuation of payments during the review process, and thereafter submit evidence to establish that she is disabled under adult guidelines;
3. a recipient of Social Security disability benefits is required to notify the Social Security Administration promptly of any change in address and failure to do so can result in problems receiving benefits; and
4. the Social Security Administration's payment center will likely review your income level to determine whether your sister may still receive SSI payments, because the amount of household income is one of the factors considered when deciding whether benefits may be paid.
I hope this helps. Please let me know if there is anything else I can do.
Paul W. Hunn