Roomrent Bro, I assure you they will get the visa. Don't forget to send them the documents from your hospital (Doctor) mentioning the delivery date of the baby. Besides that, you write a letter (kind of invitation) saying that your inlaws would be staying with you and you will be bearing any financial responsibilities during their stay here and assure the visa consular that they will return back on the legal time frame (which is abt 6 months, if it is not extended).

Paagal haru j pani bolchhan, kei thaha chhaina, All the above comments are based on my personal experience.