How was apu born?!?

So from what i understood, apu cannot have conjugal relationship with malay without killing him...in that case how did her parents conceive her? how did her dad not die from being with her mum? 😕 can someone answer me?

cvs must know that or they must have any logical explanation to that
even kalpana,her sis is a vishkanya by birth  then how bth married and had a child
but kalpana fed appu a lot of poision from childhood making her more stronger and full of poision.so in this way appu is difft frm both the mom and mausi this is what i think

Apu's naani tried to remove poison from Appu's mom. Which she thought she did and she got her married to Appu's dad, but a little poison was still there in her, which slowly killed her father.

It was told in the story itself that vishkanyas were created by injecting poison slowly & steadily which made their body full of poison. And then in the later times it became a genetic character. Appu's Nani was a Vishkanya too & as such Appu's mom (Nilanjana) was her descendant Vishkanya as she was d elder daughter. Appu nani had conducted some ceremonies to remove her daughter's poisons & after doing so thought that her daughter was a normal girl & got her married but she was wrong as some poison was still in her which killed her husband later on & among Appu & Tapur , Appu was d elder so she became a vishkanya. Yes kalpana used to feed her some kada which made her more poisonous.
Tried to explain in detail as much as I could, hope this helps. 😳