How to tell if an egg sac is viable or not?

[Wolfieskeeper18]

Hello, I have a Tigrosa Helluo and she laid an egg sac on Dec. 23, 2020. she's carrying it around like normal behavior but I was just curious if you can tell if its viable or not? If I look closely sometimes I see it shake slightly like theres movement coming from inside but I don't know if it's her moving it with her spinnerets or if i actually see movement from the babies. I understand that they typically watch over/carry the egg sac for around 20 to 40 days so if it is viable I hope to have babies soon. I just don't know what to do with them when they get here my mom says to let them go outside since they're a native species. But I hope to keep one or two at least.

 

[Poonjab]

If wild caught, then high probability