I’ve come across something kind of interesting and wondering if someone has an answer. From seed I’m growing 2 LA Confidential, 1 Maui Wowie and 1 NY Desiel. 1 LA Confidential has stretched a lot and is showing very little growth in the axillary leaves and has a thicker stem. They are all the same distance from the light, same watering schedule, ect. I’ve read male plants have thicker stems and less leaves, so I’m wondering if I may be looking at very early signs of a male? Or could it be genetics even though the other exact strain isn’t showing this? They are all photoperiod, feminized, germinated within days of each other and purchased from a reputable source. I posted 2 pictures to show the extreme contrast of the 2 LA Confidentials.
They’re probably too young to make any assumption yet. I’ve had 2 phenos of the same strain that did the exact same thing, 1 was tall and leggy, the other was short and squaty. So many things (from what I have experienced, please don’t just take my word for it) can effect the growth pattern of two plants of the same strain. One could be more sativa dominant, one could be taking in nutrients at a different rate, etc. Unfortunately the best fail proof way to determine sex is when they decide to lift their skirt / or open the trench coat and show their genitals. 
Growth characteristics at such a young stage are not indicative of sex. It is more likely to be phenotype differences. Think about individual cannabis plants as cousins (at best.) Few of us look much like our cousins.
The plants are far too young to sex.
