Should not be any if this was the transaction. The lender needs to know the source of funds your mother has available to her in connection with the loan transaction. They need to know if it was a gift, a loan, or something else. It impacts your mother, not you.
The response given is not intended to create, nor does it create an ongoing duty to respond to questions. The response does not form an attorney-client relationship, nor is it intended to be anything other than the educated opinion of the author. It should not be relied upon as legal advice. The response given is based upon the limited facts provided by the person asking the question. To the extent additional or different facts exist, the response might possibly change.
I am guessing that your mother's lender wants to make sure she has enough cash to close her deal. It wants to make sure that the $3k is a true gift and not a loan to be paid back. Assuming that is correct, your statement affirming the gift should not cause any legal problems for you.
It's fine if the cash was a gift. Your mother's lender wants to know if it was a loan that she's obligated to repay.
Disclaimer: Please note that this answer does not constitute legal advice, and should not be relied on, since each state has different laws, each situation is fact specific, and it is impossible to evaluate a legal problem without a comprehensive consultation and review of all the facts and documents at issue. This answer does not create an attorney-client relationship.