To make sure your thread gets optimum views, and consideration, you may want to post it in a discussion forum such as "health." That said, we've been dealing with similar issues with our beardie, and thanks to this forum, I've learned that our UVB source was not good quality and this has effected his growth (or lack thereof). We've since made some significant (but relatively easy) changes to our enclosure, and our beardie is doing much better, eating more, sleeping less and finally, growing.
Do you happen to know what type of set up your friend has? Is it similar to yours, lighting in particular?
Again, I suggest you post this in one of the discussion forums (a moderator may go ahead and move it as well). You may also want to try doing a search for something such as "growth issues." I actually found most of my helpful information from searching previous, or on-going threads. The growth issue is not an entirely uncommon one, and this board is a wealth of helpful information, and people!
The best of luck to your friend's beardie!
Em