Indica vs Sativa dominant strain seedlings

I tried a quick search for this but couldn't find what I was looking for.

I have two white widow seedlings and 2 thai haze x skunk seedlings. The white widow is about a week older then the thai haze x skunk.

I noticed that the thai haze x skunk (sativa dom) is MUCH taller then the WW grown in the same temps, distance from the lights, etc. Its not horribly taller, but borderline stretching in my newbie book. This happened within the first few days of sprouting and now it is just developing the first and now second sets of true leaves and isn't stretching anymore except starting to get to its 2nd node.

So my question is - is this normal for sativa dom strain? Just seems that if it were the conditions creating it - all four would be stretched - not just the two of the same strain.

If pics would help I can get them up - but didn't think they were really necessary.

Thanks for anyones time!

Bump for some help

WW has much more indica in it compared to the other so I think everything is on target that way. Depending on how long you have been growing your Haze you might want to tie off the different branches and have it bush out or tie the whole thing over. Is it CFL? You don't want to get to a place where the Widows aren't getting enough light and the Sativa is pushing the height of your lights up and away. If you have HPS and some extra lights down below then you proabably have nothing to worry about. There are a lot of tricks for working with the Sativa's height and keeping it under control but its certainly going to be a lot taller than the WW.