Perhaps the Eternal Mother had sensed that Bai Xiaochun's pursuit of his own Dao was the only hope for her and the Eternal Immortal Domains!
If he failed, then the Eternal Immortal Domains would be doomed, and no one would be able to save them. After all, even when she was in her prime, the Eternal Immortal Domains could only delay the inevitable catastrophe, not prevent it completely.
But if Bai Xiaochun could succeed in his search for his own Dao, then although there would still be many variables at play, there would at least be hope for the future.
Therefore, how could she possibly allow someone to disturb him in a critical moment of cultivation? Years had passed since she was originally injured, and left with only a bit of godly power, most of which she had given out to approve of celestials, or to help the Saint-Emperor. However, she still had a bit left to make a move in this critical moment!