All will be well when the day is done
The one where Yu Ziyuan time traveled but she thought that it was her visions of her alternate life.
She learned that there is a brat named Wei Ying who brought destruction to her and her family's life.
And so in her present, she vowed that she will never allow that to happen.
In which Yu Ziyuan found the four-year-old Wei Ying, newly pushed out of the inn where his parents left him, and decided that no, this child must never be associated with her, her family, and their sect at all.
And so Yu Ziyuan thought that she could bring him somewhere where someone may or may not find him but definitely far from where her husband could find him. If he's lucky, he'll survive that winter, if he's not, then death awaits the fevered child.
This is the extent of mercy that Yu Ziyuan could give a child.
With this, she'll raise her children without having to deal with a brat that brings trouble where he goes according to her visions of her alternate life.
Like the tag stated, this is definitely not Yu Ziyuan centric.