There was one kdrama which I watched years ago but now I have completely forgotten the main story and name.....I just remember some parts of that drama and it was like :
ML has a family who had medical shop (basically it was the shop of his aunt, maybe) and when ML was small his mother left him and went abroad and used to write letters but later he realised it was his aunt who used to write those letters and gets really heartbroken..... In the meantime....his mother comes to Korea and later everything gets okay between them...and when his mother was going back he comes with FL to show his mother, his to-be/ girlfriend....
Sorry I really don't remember things properly or in sequence so if anyone can figure this out then please let me know!!!