Congrats on the horses!
Horses are lots of fun (As long as you have the money for them! Goodness knows they can be expensive, especially here in NJ)
Anyways, I would love to be able to start with a horse from the day it is born, or even a very young one, but I do not have the time right now and probably won't for quite a few years. I've been horse back riding since I was eight nad have owned my own horse since I was ten and I still don't know all there is to know! I always learn something new!
When my other horse passed on, I was really thinking about buying a 2 year old broke black QH. She had wonderful lines, but then I thought about it and the price he was asking and realized it wasn't worth it. She had 00 feet and had already been ridden quite a bit. I didn't want to take the chance that she would one day become lame because of it.
My main recommendation is to wait until their knees have fully closed to do anything with them. Some big jumper people I have talked to wait until their horses are four or five to do any major jumping! I was very surprised to hear this! I don't think you have to wait that long, but I think one of the two biggest mistakes people make is breaking a horse too soon. The other is treating those cute little horses like dogs, because believe me, they regret it later! lol
A friend of ours had a mare that gave birth five years ago. He used to wrestle that foal and play around with it all the time. As an adult she still wants to do that and she is nearly 16 hands! Beautiful horse, but he also let her founder and she is unrideable because he doesn't want to do anything about special shoes. Never really trained her either.
Anyways, good luck! I agree with carriebrown, that sending them out is a really good option, especially with a first time horse. When I got my first horse, she was 6 and we made so many mistakes with her, but it was definitely a learning experience! Now I know so much more and that has helped me so much dealing with my new 6 year old gelding.
Do you have pictures of the other one? What breed are they?