I had it really bad for about 8 months last year. I did a number of things, so I don’t know if one worked better than the other but I totally see it as an all aboard mentality.

Get a foam roller and a tennis ball or get a pack of massage balls on Amazon, esp one with the spikes. Habe her massage the calf with the roller and balls. Find a spot that’s really tender and hold it there for 30-40 seconds. Then find another spot. The calf is the key. It controls so much more than we realize. Do that daily. Get a boot from cvs or pharmacy and wear it at night with the leg elevated. It might be painful as it’s gettirn used to it but keep wearing it. After about two weeks she’ll notice it’s getting better. The boot keeps your foot in the proper alignment for the torn tendon in the bottom of the foot to heal. It does take time so it won’t be an overnight fix. Also get some new shoes. I personally started using the New Balance Vongo? And literally my foot felt so much better at the end of the day. Expensive but oh so worth it. If she wears heels daily that can be a big part of the problem as your feet are in a plantarflexed position which isn’t natural for long term use and puts a lot of strain on the calves. Also work on strengthening the anterior tibialis muscles which are on the front of the lower leg, basically the shin muscles. Again your over powering calves are pulling on those torn tendons in the foot, stronger anterior tibs will help offset that. I would also suggest start doing hip thrusts on the floor to strengthen the glutes. The butt muscles help us with so many things daily, they aren’t just for looking good. Sorry it’s like a long ramble but I wish plantar fasciitis on no one. Except maybe democrats.