How many days are you planning to take on the route.
The average is around 12 days at 16 miles a day.
Through the Lakes it tougher going with much ascent and descent, some of it very steep.
You don't make it clear whether you and your daughter have previous experience, but in preparation for the C2C, one would hope to have at least several walks of well over 12 miles completed and preferably over 16 miles.
Many greatly under estimate this route and flounder before making it through the Lake District, due to poor preparation.
June is not far away now, I would make an extra special effort to increase regular walking mileage, to avoid the long trip over here ending in disappointment.
I'm not trying to be a killjoy, I'm just hoping you have a really amazing experience and don't become yet another abandonment statistic.