J.F.
You really cannot take the anedotal information that you will get from other Moms and apply that to your situation. Some will do better than others, and some will not do well at all. There are many factors that will predict the outcome for your sons. You do not seem to me to have all the information that you should, and I would suggest to you that you don't rely on a "theory" for what is going on here. Find out for sure by going to see a Developmental Pediatricain ASAP. Make the appointments on Monday, and do not delay. Call your nearest Children's hospital, and ask to be seen by a Developmental Pediatrician, do not settle for a psychologist, or therapist who could see them sooner, get the appointment and ask to be on the cancelation waiting list. This will take many months, but you need so much more information than you have. The Developmental Pediatrician will call in every type of professional your sons need, from speech, hearing, language to OT and geneticists. Then, they will put all the information into one report with a complete treatment plan for you to follow.
Next, get as much therapy as you can get until you have this appointment. If you can get OT and speech privately, get it. Do not settle for only what the state will provide. The one thing you have going for you is your son's young ages, do not waste a single second of the time they have on thier side. This will be the biggest predictor of how well you sons do, how early and how much intervention you get, and being sure that you do not miss a single thing in their treatment. The state has no interest in getting your sons the best treatment they can get, they are only interested in providing what is required by law-You will always want more, and they are not required to maximize your son't potiential, and that is what you want.
It may very well be a struggle. I don't say that to make you feel bad, but it is probably reality. I know you want to hear tons of Moms say that they got therapy and thier child is fine, but for most of us, that is not the complete picture. Do not count on being that one parent whose kid is like the few you will hear about who are not effected later. For sure, do not delay a single day in getting more therapy because someone writes here that thier cousins sister in laws neice had this problem and is now a rocket scientist. You could be very disapointed, and you will never get the most important years back if you wait. More is much better than less. Now is far better than later. NEVER wait and see because you probably won't like it.
It is far too soon for you to worry about school age, get a diagnosis from a Developmental pediatricain, and get as much therapy as you can get in the mean time for the symptoms that you see now. Don't waste a second, time is all you have that will be free.
I am very sorry if this sounds doom and gloom, it is serious, but many people live with these kinds of issues, and they have very happy lives. You will have plenty of time later to worry about the future, concentrate now on what you can do when intervention is hands down the most effective.
M.