Unfortunately, they are not old enough. I do not really have good news for you. I will explain in detail your options. There are 5 ways to come to the U.S. to live permanently. They are through family, through employment, through asylum, through investment, or through the lottery.
For family, it must be immediate family such as U.S. Citizen spouse or U.S. Citizen children over 21 in order to be able to come immediately. U.S. Citizen or Lawful Permanent Resident parents or U.S. Citizen siblings, or Lawful Permanent Resident spouses can also help you, but the wait for that is about 4 to 12 years or so.
Through employment, you would have to generally prove that you would not be taking away a job from a U.S. worker and the less experience and education you have, the harder that is to do.
Through asylum, you must prove that you will be persecuted, tortured or killed if you stay in your country and that this will happen to you because of your nationality, race, religion, political opinion, or membership in a particular social group, not because you would run the same risk as anyone else in your country to fall victim to a crime or bad economic conditions.
Through investment, you are looking at generally $1,000,000.00 for a residency, or $500,000.00 in an area designated as a high-employment area, plus in both cases the investment has to create 10 or more jobs for U.S. workers.
And through the lottery, it would be very difficult to win one of the 50,000 visas available per year and some countries do not qualify.
There are some visas available where you can stay temporarily and then later change to Lawful Permanent Residency if you qualify.
Some of the visas available through employment (if you have a job offer and you qualify) are:
H-1B for professional workers
H-2A for seasonal agricultural workers
H-2B for seasonal nonagricultural workers
H-3 for industrial trainees
Then there are the F-1 and M-1 for students and J-1 for exchange visitors.
And then there is the E-1 for treaty traders and E-2 for treaty investors (these types of visas are not available in all countries).
Here is a link to most of the available non-immigrant visas:
Since you have a college degree, it seems that you are eligible for an H-1B visa. You need to get a job offer, though. The job offer must be for a company that is offering a position that is related to your degree and experience. The position must normally require a bachelors degree or higher. The company must have a need for someone in that position and must have the resources to be able to pay you what is normally paid to someone in that position. Also, because they are used up for this year, you will need to apply on April 1, 2014 to start working on October 1, 2014 or later. The exception is if you apply for a cap-exempt job and those are at an institution of higher education or its affiliated or related nonprofit entities or a nonprofit research organization, or a government research organization. Those are not subject to this numerical cap.
Here is an official link to the H-1B:
I am truly sorry. I know that even though there seem to be many options, they are not easy. I wish I had better news for you. Your mother can file for you, but it will take about 10 years for you to be able to immigrate that way. Please let me know if you have additional questions and please do not forget to rate my service to you (not the state of the law) as that is the only way that I can get credit for my assistance. Even after you rate the service, I can still answer additional questions for you without additional charge. If you do rate me positively, a bonus is always appreciated. If you would like to request me in the future, just go to http://www.justanswer.com/law/expert-guillermosenmartin/. Thank you!