leaf growth patterns

differently how?

If its number of fingers on them, or shape... it's just genetic variation. If you mean it in a bad way, like they are stunted or deformed, it's likely the same cause, but might actually be cause for concern.

 

is one plant producing long skinny leaves and the other fat wide leaves? if so you have a sativa and indica dominant strains growing.

 

Several of my plants have upper leaves that don't look at all like MJ, heavy and mis-shapen.

 

you may have a mutant on your hands. hard to say without pics...