Rom where the female lead becomes a stepmother. 

Currently watching Unforgettable Love and loving every episode. :) 

 kwoon:
Rom where the female lead becomes a stepmother

Five Enough/Five Children - I cannot emphasize enough how good this one is. Both the ML and FL become step-parents, and watching their blended family grow is so adorable.

The Charming Step Mom - One of my first dramas! The romance is more slow-burn, but the children play a huge part in their relationship.

Prime Minister and I - It's been a long time since I've seen this one but it was very cute and I remember the leads were fantastic.

Currently Airing: Young Lady And Gentleman - I've been watching this one for months, and these kids are adorable! Such talented young actors/actresses. It does drag on a bit at some points, but the sweet familial moments are worth it in my opinion.