@thelyingcandor Just as a test can you try relocating the family to a different house to see if that clears the issue? If it works you can move them back again and if it does not work you can just exit/ go back to the main menu without saving. If the toddlers are temporarily glitched then maybe this will fix it.
A slightly more extreme test would be to save the entire household to your Library, start a New Game, import the family from your Library, and play them a bit in this new game to see if that will clear the issue. You can just exit without saving either way. If everything looks good in a new save then maybe there is something going on in your old save.
Lastly, are you using any mods or CC? If so then you might want to temporarily remove them to a storage folder somewhere like on your Desktop or an external drive, delete the localthumbcache.package file from your Sims 4 folder, and then load your game to see if the problem goes away. Do not save your game while your mods and CC are removed, this is just for testing. If the problem goes away then maybe you have some outdated mods or CC that need to be updated and replaced.
Good luck, I hope we can figure this thing out :D