Well, if she leaves her child behind, that would be a strong tie to her country that she would not easily abandon. So her chances to be granted would be increased. They want to make sure that she will go back after her trip. If she is willing to do that, she can apply, prove it and see what happens. If she is denied, she can just apply again because there is no appeal process. Usually they like to see a 6 month period between applications of B-2 and B-2 (not B-2 and anything else as you will see. If she is denied B-2, she can immediately apply for a different visa if she likes, she doesn't have to wait). If she is denied or if she wants to avoid that alltogether, then there are three other options for you to bring her:
1) The K-1 fiancee visa takes 6 to 9 months, but you must have met before during the last two years in order to process it. The I-129F will cost $340 plus a $350 fee for the visa processing fee. After she enters the U.S., then you have to marry and then you have to pay $1070 for the I-485 and she will have to wait about 5 to 7 months and gets another interview that you attend with your new spouse so that she can get Residency.
2) The K-3 spouse visa takes 6 to 9 months, you must be married. The I-129F will cost $340 plus $420 for the I-130, and $350 for the visa processing fee. Then after she enters the U.S., she must still file the I-485 for $1070 and wait for the marriage interview about 5 to 7 months later.
3) The CR-1 visa (or IR-1 if your marriage is more than 2 years old) takes about 1 year or so. You must be married. The fees are $420 for the I-130, $330 for the visa processing fee, $88 for an Affidavit of Support fee. But once she enters the U.S., she enters as a Resident and she does not have to file (or pay for) an I-485 nor does she have to attend an additional interview. She just gets her green card in the mail a few weeks later.
So the K-1 and K-3 are faster but generally more expensive. The CR-1 (and IR-1) are slower, but generally cheaper. And no, there is no middle-visa that she can use to enter the U.S. while that process is pending. She will most likely have to wait outside.
Here is a link to all three:
I know you do not want to wait. I know it is very inconvenient. I know you want to be together sooner rather than later, but I have this same conversation two or three times per day on this website. No one ever likes it and believe me, if there was an easier or faster way, I would tell you. I know you will probably say, “but what about this...?” or “but what about that...?” But I will most likely continue to have bad news for you. I am truly sorry. The problem is that the U.S. concerns over security and fraud in this area are more important than a 6 to 9 months inconvenience to you. The way they see it is that if it truly is a real relationship, it will survive that length of time apart. Again, I am truly sorry. I wish I had a faster and easier way to tell you about.
If she still wants to apply for the B-2, she should make no mention of a relationship with you because that would decrease her chances of approval.
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 to you. 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/ and make sure you type: FOR GUILLERMO on the subject line. Thank you!