From the facts as you have communicated them to me, I think you should do three things in respect of your new application:-
1. Submit the birth certificate for the child, I presume this states that it is yours. If the birth certificate is in another language other than English then you will have to get it translated by one of the UKBA approved translators before you submit it with your applicaiton. As to the other documents you mention in your most recent post you should ask a local solicitor to draft a witness statement for you referring to the birth certificate, that the child is yours and submitting the further evidence as proof of parentage. Certified copies of documents will be annexed to the witness statement and you will have to sign/swear it in front of a solicitor.
2. Explain why you did not mention the child in your intial interview. It would be best if you could plausibly claim that you did not understand the question or that it was a mix of this and your honest mistake. Perhaps you were confused and thought they were asking if you were bringing your child here at that particular time.
3. If the income that is available to you is both yours and your husbands then you should make sure you detail this in your application and evidence it by submitting proof of that income. This should be in the form of bank statements, evidence of employement, tax returns etc. basically anything that is documentary proof of the income.
If in doubt about whether to submit a document, generally the best policy is to submit it.
Provided there are no other defects in your applicaiton you shoudl be fine, but you may ask for a solicitor to either draft the applicaiton for you (£800+Vat approx) or to check the one you have drafted (£350+Vat).
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