Welcome!
Given your backgrounds, I expect you know that some of what you are experiencing is just developmentally-appropriate (I mean for your developmental stage as parents!), with the added layer of highly verbal and inquisitive tiny people. Yes, you will sleep again some day. Yes, you will have quiet and free time again some day. But probably not for many years.
Actually, I think a lot of us find that once children become independent readers, the constant demands for information and stimulation change; some of those needs can be met with a stream of books.
And I would encourage you to think about why you are worried about a younger child being even brighter, or about future concerns. I am not downplaying the very real complexities of parenting a GT child--just suggesting that there is plenty to take care of in the moment; no need to borrow trouble. There are as many joys in parenting (any child, not just GT) as there are sorrows--more joys, I believe. (And I say this as someone whose extremely darling adolescent is giving me small fits at this very moment!) Enjoy the delights of these years while you can.
