The Red Fletch - Heroes of Sherwood, #1

You thought you knew the legend of Robin Hood... When Alys' older brother Hob leaves England-and her-to follow Robin of Locksley to Jerusalem for a Holy War, she expects Robin to do all he can to bring her brother home safe. Robin returns and causes havoc in Nottinghamshire, threatening everything Alys holds dear. Hob is still at war. Her family has lost their home. Alys blames Robin for everything. The Sheriff of Nottingham promises Alys that, with Prince John's favor, he has the power to bring Hob home and restore their family to their village farm.
All Alys has to do is infiltrate Robin's band of merry thieves to help bring the outlaws to justice. Alys is confident she'll have Hob back within a year.until she discovers everything she thought she knew about the outlaws was wrong.