I'm impressed by the actings: Jin Ji Hee plays really well until the end, The last scenes of her are really amazing. The same goes for Lee Min Young.
The story is really nice and even tho I've read the manhwa I really liked how they adapted it.
I really like the dynamics of the parents towards the children. Episode after episode you end up understanding each of them better.
Finally, I really love the main couple; really sweet. the chemistry between Sung Hoon and Jung Yoo Min was really present from Episode 1 to episode 12.