Both are mini dramas in which a couple breaks up due to a misunderstanding, lies, and scheming from relatives. The FL then returns with a stronger, more jaded personality. In both, one of the parents was unaware they had a child or thought the baby died and discover that they now have a five year old child who helps brings the two back together.
Both are short length dramas in which the ML treats the FL coldly, blaming her for something she didn't do, and the two separate, with the FL giving birth to and raising their child alone. A few years later the ML finds her and their son and brings them back to his home. Both have rich ML/poor FL, a SML pursuing the FL, and scheming relatives of the ML.
Both are mini dramas in which the couple breaks up due to manipulation by the rich ML's relatives, and the FL, who is poor, gives birth to and raises their child alone. Five years later the couple crosses paths again and begin to grow close, raising their child, all while dealing with the ML's relatives.