I cannot describe to you the feeling that you receive when you look at a child and know that they are yours.
Since I do not know any better, I believe that it's different from delivering your child. In delivery you already know the child is yours. You have been preparing yourself to bring your child home for at least 9 months. In anticipation you prepare the room, buy clothes and imagine your life with a new little one in your home, forever.
For couples in our situation (Andrew and I) its almost a discovery. You find yourself counting heads that are missing, or standing in empty rooms wondering what you're up at 4 am because something inside you told you it was time to rock the non-existent baby to sleep. You feel an urge that your child is somewhere on the Earth already and you need to find them. The search can be frustrating, it will fill your heart with emptiness when you feel you've failed in your quest. (No, I'm not crazy. Just trying in some way to describe what it's like.)
In the times that you do succeed; the healing of your heart becomes filled. So quick is the change that you can feel it in every step you take. The pain and anguish of so many years and months is suddenly transformed. You realize the suffering can be left behind and you can join in the happiness that so many couples have already received.
The spark of life gleams on a new mother who recognizes the struggle it took to find her child. For the new parents, no matter the age, when you see them, hear them, your heart recognizes the sound as clearly as if you had never been parted.