Some members here have young children and their birds but its up to you to educate your children about the grey, to stay a safe distance away, not to poke fingers in the cage and so on and so forth. Personally I would like for you to wait a few years when those children will be a little older and more inclined to obey the rules around greys but if you decide to go ahead then you must do your best to make it work out, its not easy as the other members will attest to but it is feasible.
Greys do tend to bond with one person but if you get a baby grey and socialize it properly then a good relationship can be formed with all members of the family, my grey is bonded to me but she tolerates my husband and actually gets along better with him now than she used to in the early years.
The important thing is can you manage it now, I know your human children come first but when you take a grey into your home and your life you don't want to go into that with the notion that if it doesn't work out you can rehome it, too many of them end up that way so its up to you to figure out if you can manage both.
Good luck to you and let us know what you decide.