Zodiac Girls: Brat Princess by Cathy Hopkins
This time, it's a Leo!
Leonora is a rich, pampered princess - she loves to be the centre of attention and to have her own way. Her parents have had enough of her behaviour and decide that it's time for some tough love: Leonora is going to brat camp. She's got to mend her ways and become the angel her parents always hoped for! But when Leonora is picked to be a Zodiac Girl the planetary powers take over - and they mean to get results!