Edit 22/8 New Customers can get extra 10% Off with code SPAAUG241 making it £134.10 for family of 4!! Thought this an amazing offer for what you get for the price of £149 for a Family of Four (that's the total price, it works out at £37.25 pp!).
They have a few other really great offers on incl spa days & spa breaks, will link to those in 1st post.
Staying at the Mercure Brandon Hall Hotel And Spa, Warwickshire in a Family Executive Room, you will get dinner, bed and breakfast, use of the hotel leisure facilities, 20% off any pre booked treatments and 2 adult and 2 childrens (4-12 years) entrance tickets to Warwick castle.
Facilities include: Indoor swimming pool Sauna Steam room Relaxation room
Check in time 2pm, check out time 12pm. There seems to be dates available for August, Sept, Oct & November, so plenty of time to take a break.