Xia ruofei was not blindly confident. It was just that Ling Qingxue's cultivation had also reached the peak of the third Qi layer. From the third Qi layer to the fourth Qi layer, it was not too difficult to break through the bottleneck. Furthermore, after taking the heart concentrating grass, Ling Qingxue's physique had become very suitable for cultivation. With one night's time and the help of array flags, it was completely possible to help Ling Qingxue break through.
After all, Ling Qingxue's talent was actually better than Song Wei's after consuming the heart concentrating grass. This was also the main reason why she was able to catch up even though she started cultivating later than Song Wei.
The facts had proven that Xia ruofei's judgment was very accurate.