Hmm, working for a close family member is fraught with difficulties, even if you believe that your are starting with clear cut rules and there are so many questions that need answering. In your current job, as an employee (I assume) you have certain entitlements, paid holiday, SSP, pension payments etc. If you work only for your daughter, it is debatable if HMRC would accept that you are a self employed person, as you will only work for your daughter. If your daughter becomes your employer, that is far from straightforward too.
Either way, I would be reluctant to take on such a role, partly because the terms offered are not good and partly because I suspect that it will become impossible not to blur the lines between business arrangement and family ties.