There are two issues here. The first is very serious for you, and the second may be even more serious for your mother.
First: In your prior visa applications, you answered "no" to the DS-160 question about your mother being in the US, while the truth was that the answer was actually "yes." The US State Department will have your prior visa applications, and will see that your answers are different. They will also easily see that your mother is now a legal resident in the US, and because of her recent status acquisition date will know that she may have been in the US when you said she was not. Your earlier answers will therefore be seen as a misrepresentation by you, and as Traveller observes, you're very likely not to receive a visa. I'd expect you'd earn a long ban as well.
Second: Because the State Department will see that your mother might have been in the US when you said she wasn't, the State Department may look more closely at her. They'd be interested in whether she made misrepresentations in her status paperwork and application documents. If she did, and they can show she did, her US resident status could be at risk.
Thus: your application for a US visa could have very high stakes for both you and your mother...particularly for her. For these reasons, do not file an application for a US visa until you have had a consultation with a US attorney who is experienced in US immigration matters.
After you've had that consultation, follow the lawyer's advice.