Hey buddy....chill
who says that 2 bodies with similar charges cannot attract each other??????
Yes , it can be possible if charge on 1 body (let say A) is much much larger than charge on the other (lets say B) . On account of induction , the ball B is carrying smaller charge shall aquire some net charge of opposite sign as its lying closer to A , SO B will experience some net force of attraction...
so it is possible in this way...
cheers!!!!!!!!