Tight-feeling seatbelt - short driver

My wife is relatively short (~5'). As a result, when she drives the Prius, she needs to move the seat quite a bit forward. This causes the seatbelt to feel really tight on her left shoulder because the seat is moved so far forward, and the seatbelt needs to be stretched a lot more than normal. Adjusting the height of the seatbelt anchor near her shoulder doesn't help much. She's fine when she's in the passenger seat because that seat is positioned a lot farther back, so the seatbelt feels normal to her on that side.

I was wondering if anyone else has experienced this. Is there some way to deal with it? Will the seatbelt eventually loosen up over time?

 

Thanks for the suggestions. She has the seat height adjusted to a comfortable height for her. She doesn't want it all the way up because at that height, the front of the seat hits the bottom front of her thighs. The seat length in general is a bit too long for her. I have a feeling that the Prius seat fits taller people better. It fits me well. We also have an older Camry, and that seat fits my wife well.