Have Sword, Will Travel Series

Odo (seventh child of the village miller) and Eleanor (always looking for adventure) stumble upon a sword in a dried-up river outside their village. Eleanor (strong and able) tries to extract the sword but is unable to, and it is Odo who is surprisingly successful. It is even more surprising that the sword, once pulled out, starts to talk. And rather annoying when the talking sword turns out to be rather grumpy, stubborn and, at times, catastrophically wrong....

Sir Odo and Sir Eleanor still think of themselves as unlikely knights. But when their kingdom is threatened by forces of significant nefariousness, they and their talking swords join a bold quest to rescue a monarch, vanquish deadly beasts, confound a prophecy, and (if they're lucky) avoid stepping on the tail of a very powerful dragon. 

Odo and Eleanor are now officially knights, helped (and sometimes hindered) by their magical but rather difficult to control magical swords. But if they thought life as a knight was going to be easy, they were wrong! Before they know it, their first task is to tackle some ferocious bile wolves!