We moved back to the UK four years ago. I am a British national and my wife and daughter are Chinese. We entered the UK on EEA permit from Sweden where we meet and were married whilst I was working there. My wife and daughter were issued with residence permits which are valid to 2020 and I now want to apply for citizenship for them both. My daughter attends school full time and my wife and I have a business here.
The spouse of a British citizen can apply for naturalization after residing in the UK for three years. It is not clear to me whether this applies to someone in the UK as a non-EEA national under the EEA regulations, but I think that in principle it should. The web page suggests that it does not, but I think that is an oversight or oversimplification on the part of the author of that page.
Similarly, the residence requirement for the child of a British citizen to register as a British citizen is three years. This option is only available if the child was born on or after 1 January 1983. This could be fulfilled if you resided in the UK for three years before the child's birth or if the child has resided in the UK for three years (which she has).
If your daughter must apply for naturalization, it looks like the 5-year requirement would apply to her. If she has leave to enter or remain under the immigration rules (that is, if she has a residence permit), then she may be able to apply five years after moving to the UK. If she is present under the EEA regulations (that is, if she has a residence card), then she must wait until at least six years, because she needs to have permanent residence for at least one year before she can apply, and permanent residence status arises after five years of residence. But there's a very good chance that the EEA regulations will have been repealed by that point because of Brexit, and I'm not sure whether the new EU "settled status" will result in different residence requirements for naturalization.