Plant is short?

Feb 6, 2017
So my rosetta stone for some reason stood shorter out of all the plants, they are 1 month and three days since seed. its on its first week of thru veg.what can cause its dwarfism, and it is not an autoseed. side by side comparison from 01262017 to today 02062017. 11 day difference stood the same height???
Vegetation, 1 week
Rosetta Stone, (hybrid) from Grimms Brothers (
Apollo Haze (hybrid) from Grimms Brothers (
Mystery seeds( baggies) (hybrid) from unknown