Peace Talks by Jim Butcher 

The latest in the Dresden files.  Dresden in still considered a part of the White Council of Wizards, while he is also Mab’s Knight of Darkness.  He is living with the Svartelves to protect his daughter.  And Mab has loaned him out to the most powerful white vampire.  His half-brother’s half-sister.  Then his brother goes and does something stupid like trying to kill the king of the Svartelves.   Which makes them suspicious of Desden and his daughter.  All the while, Dresden is supposed to watch out for the security of a special convocation of the magical unseelie accords.  Now the White Council doesn’t trust him.  And that includes his grandfather, the most powerful wizard of all.

The only way to save his brother is through subterfuge.  The only way to save the earth is to fight a Titan.