I would guess the letter said that it sounded as if you may have a "MERITORIOUS CLAIM" -- which means that your case has merit -- it is a valid case. For that reason they probably suggested you continue to seek legal assistance. You may have better luck with a legal aid, if you qualify. Check out a service like www.legal-aid.org.
Custody cases are difficult and because if this fact they do cost quite a bit, as I assume you are now well aware. Consider making arrangements with your current attorney and explain your situation -- he may be able to offer assistance.
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