Well, if it may interest you, not exactly a "surprise" parenting, but they are raising their kids alone.... I have a liking to single-parent genre dramas.
For ML raising kids (they all show romance between ML and FL - and her interactions with the child to love them as a mother later - ) :
Khu Khaen Saen Rak (2021)
Eccentric! Chef Moon (2020)
Fanletter, Please (2022)
Unforgettable Love (2021)
Prime Minister and I (2013)