Paen Rai Long Tai Wa Rak (2017)

Both have marriages, fake pregnancies, and jealous girls after the main leads. There's also romance where both dramas have an aunt/uncle as a main lead.

Both dramas have a male relative helping their pregnant female relative marry the man they love by forcing another woman to marry him. In this case the uncle marries a woman who is pretending to be pregnant to protect her adopted brother from being forced into marriage with the niece.

Paen Rai Long Tai Wa Rak is modern, but both the female leads pretend to be pregnant to search for clues. Both are comedic and the ML's families are welcoming to the FL.

In Wong Wien Hua Jai similar pregnancy event which lead to a marriage.
Hoewever, The differences in this is in Wong Wien Hua Jai the Male lead married the brother-in -law's ex girlfriend for his sister sake. While in Paen Rai Long Tai Wa Rak, the uncle married the female lead for the niece's sake.

In both, there's a marriage of convenience between a serious, older businessman and a stubborn and willful, much-younger woman. The men misunderstand the female's relationship with another close male. Both dramas also have rich families, scheming relatives, and a slow, hate-to-love romance with lots of bickering.