It's EVERYTHING
great advice above but little things that can help
Lavender room spray/lavender bath and shower wash/lavender under her pillow
Get her new Pajamas and bedding to make her feel like a fresh start
Change her bedroom around, again to feel like a fresh start
Have a pamper night atleast once a week together and DH if he's willing, face masks, paint nails, soak feet, hair mask - obviously with child friendly products
A sensory swing for when she's feeling stressed
Nice calming music in the home and calming lighting
Get her to do some journelling about how she feels
Get her to drink lots of water and eat healthy
A fidget toy for when she's feeling stressed
Herbal tongue spray and herbal roll on that you put on her wrist and temples when stressed or even when not stressed just to keep it at bay
Ensure she's sleeping well and if not there's stickers you can buy that aid sleep/white noise, pink noise etc
Plan future events - things like in two weeks we will go to the cinema , in one month we will go on a shopping trip etc so she has things to look forward to
Could do some kid friendly yoga together and with DH . Have a look on YouTube. There's also breathing techniques to help her
Make sure she's getting enough vitamins if she's not eating much or not eating healthy food
And of course talk talk talk
Sending love OP.