Hi Dee, apologies for the delay in getting back to you. Bird-dropping Spiders are common in suburban backyards but their remarkable camouflage means they are not often seen. The spiderlings hatch in late winter and they develop through spring, maturing in summer. The adults combine their amazing camouflage with an amazing strategy for capturing prey. Females produce a pheromone which mimics that of female moths belonging to a particular family (Noctuidae) and use this to deceptively attract male moths to their deaths. The young spiders, however, feed on a range of small insects.
At this time of year there are few small insects available, and they wouldn't normally hatch for some time. Perhaps bringing them inside has warmed them up and caused them to hatch prematurely. They are difficult to feed at this stage of development, so the best option may be to put them back outside and allow them to fend for themselves. Because they are generalist predators, it doesn't matter where you locate them - they will move around by themselves to find the best locations. Like all spiders, they are cannibalistic when very young and get by through eating unhatched eggs and other spiderlings.
The other notable characteristic of this species is the high rate of parasitism. Tiny black wasps lay their own eggs inside the egg sacs of Bird-dropping Spiders, and the wasps of the following generation drill small holes through the egg sac to free themselves. Parasitism is so high that it's rare to find egg sacs without these small holes in them, although the wasps never consume all the eggs in any particular egg sac.
Good luck and it's refreshing to see your ongoing interest in this species.