I screwed up. It's brotherbangladesh fault. If you ask me.........
Here is true stat that I have see around me:
Love Marriage.................
First child is a daughter.
F Vhai…………......……….............….…..yes
My Uncle…………………...................….yes
K vhai………………………....................…yes
C vhai…………………….............….....…..yes
R vhai………………………........................No
F Apu……………………….............……..….yes
H Chacha……………………..................….No
F Chacha…………………….............………yes
Z vhai………………………….............……….yes
S sis................................................yes
So, there in 80% case the first child is a daughter. So I suggest you to look around you considering 70% in average. And I can not give any scientific explanation as it's a natural phenomenon to me.
BTW, I am fan of those people who make true love and then able to marry. So congratulations.