N.P.
The only way to get over it, is to face it. I'd try something non threatening first, like borrowing some nature videos from the library that are geared towards kids to teach her about them and how interesting they can be. Sit and watch with her. Tell her which bug is your favorite and why.
You can get her a sticker book and buy some special puffy stickers of cute bugs with google-eyes and glitter butterflies to stick in her book.
Once she can tolerate those, I'd take her to a zoo with a bug exhibit where you can explain that all the bugs are behind glass and can't get out and that you can leave whenever she wants. Give her the control over the situation. If she wants to leave shortly after going in, check out a few other places then try the bug hut again later.
I'm not sure how old your daughter with the phobia is, the six year old or the three year old. The three year old may just outgrow it. The six year old might need the "facing her fear therapy" with videos and trips to the zoo.