First of all, please don't ask PetCo for any more advice. They know nothing. Tarantulas don't have nests!
Can you see an eggsac? It will be silk white or it may had dirt imbedded on the outside of it. It'll be round and about the size of a golf ball. You must first be sure that there is actually an eggsac before you start worrying about spiderlings. It is possible that the spider just created a molt mat or it just wanted to burrow and make a cozy home.
Assuming it is an eggsac, you'll have somewhere between 100-300 babies. These will all need to be individually housed or they will eat each other. The most economical way to do this is to go buy 1 or 2 ounce solo cups, like what resturaunts put extra sauce in. You can get a bag of them pretty cheap form restaurant supply stores or online. The spiderlings will emerge (eggsacs don't 'hatch') from the sac aftre about 60 days, give or take. When they first emerge they will be a clearish yellowinh color and are 1st instars. They will not eat at this stage. After they molt one more time and become 2nd instar they will darken up, and start looking more like a fuzzy spider. Then they will eat. They can be fed, fruit flies, tiny pinhead crickets, or the legs off full grown crickets. They grow very very slowly, a solo cup will probably make a good home for about a year, possible more.
If the mother does have an eggsac, leave her along and do not disturb her. Don't try to feed her. You can pull the eggsac
out early if you want to fight her for it. This will prevent having to find all the spiderlings in her cage after they disperse, and prevent them from escaping. If you leave it wiht her, remove her before you try to rehouse the spiderlings. When you're ready to do that, all you need to do is put a tiny bit of substrate in the solo cup and use a paintbrush to gently nudge them into it. Punch a couple holes in the lid with a nail and close it up. Spiderlings need moisture, so give them a quick spray on the substrate. It should not be soaked, but it should always have a little wayer in it.
Hope this helps, if I missed anyhting let me know.
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KJ Vezino
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