Yao Ying's maternal grandfather wanted to kill the baby out of anger after Yao Ying was born --- he felt that Yao Ying was the source of trouble, however, Qian Yu's personal servant kowtowed and begged him to let the little young master be. After all, it took a lot of effort from Qian Yu to finally give birth to him.
Shouldn't the master think about her young mistress's behalf?
If there was no that personal maidservant, Yao Ying would already be dead at that moment because his maternal grandfather was very serious because all he needed to do was throwing the baby down to the ground and he had indeed almost done that. However, at that time little Yao Ying seemed to feel something and started crying, he didn't have the heart to do that. No matter what, he was his only grandson.