Hi all.
I am looking into applying for UK citizenship for my 17-year-old daughter and myself.
We have Indefinite Leave to Remain and have been living here 6+ years.
I guess the application and fee process looks straight-forward enough.
But the initial visa process was a nightmare and you guys were extremely helpful.
Any tips you could give would be fantastic! 
Also, will I need her American biological father's consent? If so, how do I go about doing that? Is there an official form?
Thanks, all!
You did see the straightforward enough application form right?
She is applying on an MN1 form and there is a place for father's consent. Ask him to print out this page and sign and post to you then put it into the application form (never mind letter size/a4).
If she is American I'd take care if possible to apply in such a manner that she is registered before she is 18, because taking an oath of citizenship to a foreign country is possibly an expatriating act (and especially with Trump and all).
There is a traditional exception to those married to a foreign citizen and naturalising in their spouse's country but that is not true of your daughter.
I am a British lawyer not a US lawyer so this is not legal advice, but if you are NOt in the UK due to marriage you need to give it a thought in re naturalisation.
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Disclaimer: I am a Level 3 OISC advisor and so my opinions are informed by knowledge of the law and years of practice. Yet, no opinion given without detailed review of an individual case should be taken or treated as competent legal advice.