My broody moulted in the separate pen too, then came back into lay about 8 weeks. I put ad lib chick crumb in a hopper and a handful of mixed corn in at night as I do for the rest, but I also bought some mixed wild bird food with crumbs of nuts, mealworms etc and sprinkled a little of that for her to scratch about and find during the day, both she and the chick loved it and I thought it was a bit of an expensive treat but the Mealworm mix was from Morrisons and not that bad for a kg bag. The odd sunflower seed and raisin also found their way into the pen and tho I move the pen alternate days as you do, I also pulled up a few grass clumps by the root and dropped them in on the odd day so there was soil and perhaps an odd worm and bit of grass to play with on non moving day too.