I wear these over my socks in my shoes during winter months of riding. They work incredibly well. When you first start wearing them they are noticeable but after a couple weeks of wearing them you forget they are there. https://www.amazon.com/Hot-Sockee-Neoprene-Warmers-Construction/dp/B076B4PDZR/ref=sr\_1\_3?crid=107VI0GUEU5PJ&keywords=hot+sockee&qid=1666986945&qu=eyJxc2MiOiIxLjg2IiwicXNhIjoiMS4zMyIsInFzcCI6IjEuMDgifQ%3D%3D&sprefix=hot+sockee%2Ca...
Maybe try neoprene toe warmers? I’ve been thinking about picking up a pair but my merrell boots have been keeping my fee warm enough so far.
Hot Sockee - Neoprene Toe Warmers - Worn Inside Shoes or Boots - 3 Sizes - Cycling, Hiking, Winter Sports, Camping, Work & Construction Boots https://smile.amazon.com/dp/B076B4PDZR/ref=cm_sw_r_cp_api_fabc_N5BYFbX6GP9N0
I wear wool mittens and keep my thumb in with my fingers.. Game changer. If it is really cold, I'll put hand warmers inside, but usually the wool mittens themselves are good enough. What I would recommend is neoprene sleeves for her toes.
Something like this:
I used to have major issues with my toes and this completely changed that.