i`d put them both on a 24/0 light schedule until the younger of the two is mature enough and big enough to flower!!
ignore the fact that one is showing flowers -- i`ve had plants show female pre-flowers at 3 weeks into veg!! They won`t start to flower PROPER until they been on 12/12 for a week or so. Keep them both on 24/0 and then put them on 12/12 when the younger of the 2 is mature enough.
What i`d do anyway!
Digi