You can't add back what is not there in any photo. There are some filters and effects that adjust portraits to give the illusion of softer skin, if that's what you want.
There are two web sites with forums where people will apply their best skills to improve a photo if the cause is worthy. One is called Ugly Hedgehog and the other is a software and retouching section at dpreview.com
Good luck! My wife and I adopted two children from overseas. The challenges were unbelievable and overwhelming.
........ Thanks again and I hope your enjoying your bundles from overseas
They're both about 40 now. One is OK the other a wreck. In order to adopt, parents have to convince themselves their skills will be great enough to mold and shape a personality. After awhile they have to accept that the gene set in the child is by far the dominant influence their abilities, attitudes and outlook.
Back to the topic.... If you want, put the picture on dropbox or somewhere and I would be happy to try some photoshop on it. I'm fairly low on the experience scale, but you never know!