Oh congrats to you , I had a newborn and a 13 month old, and although a little tiring , (also had a 3 year old, just), you will be fine. Was a little expensive for two in nappies for 1 year, but try to save now.
I had a boy then a girl close together and it's great, a bit like twins, where you do more trips to different gaes groupl clubs for 1 year , then they are in the same group eg Cubs now so same times for pickup etc , rather than different. It is a good age gap actually , I don't think they see it as any gap at all, so they have their rivalry.
You will love it, so will they! enjoy X