so i got my first tarantula, an euathlus sp. about half a year ago. a couple months in she developed a bald spot although i've never seen her flick hairs. i assumed it was alright though. about a month ago i got a second tarantula, a juvi chaco golden knee and i saw today that they're developing a bald spot too! again, i've never witnessed them flicking hairs. which leads me to believe it's something wrong i'm doing in my care for them? does anyone have any ideas about what i could be doing wrong?