We grew up with our mum using dog flea shampoo. Animal shampoos are sensitive for skin and worked on all ages. Doesn’t sting like some of the lice branded ones. Just the stigma attached but when something works, who cares. I use it for all our family now.

Use a hair straightener- make sure you thoroughly comb out area closest to scalp, as you won’t be able to get right to the roots with a straightener, but on the lengths, it kills the bastards and the eggs too- maybe not a good idea on very little ones though as you don’t want to burn anyone.

Honestly we have had so much lice in this house I'm now an expert! My ex shacked up with someone with hair down to her waist same as her 2 daughters they never tied it back and I worked out they must have just lived with lice and gotten used to it because without fail after their fortnightly stay my kids came back with lice! All I did in the end was thick white conditioner and nit comb each night till they were gone worked really well and didn't need any chemicals

Boil or replace all hair brushes, combs, accessories. Hot water wash all hats, caps are top rack dishwasher safe. Hot wash all linens and pillows.
Glob cheap conditioner on all their heads and put them in shower caps. Leave them in front of a movie for 30 mins or longer. Rinse, nit comb, wash as usual.
One you get lice you're much more likely to be reinfested for up to 6 mos. A tea tree oil shampoo and conditioner, even a leave in conditioner or detangling spray will keep them at bay.

KP24. It's napalm.

Yes they are yuck, but you really need to just accept that yourkids are going to get them loads more. Even after treatment. I use the maldison based treatment, and a week later the pyrenthins(?) based one if I see tonnes still in the hair

Put the hair in sections, straighten the hair on real hot setting, then comb that section. Repeat each section.
Wash Everything!

It is horrible. The first time my kids had nits it went on for weeks. Make sure you swap treatment brands as they contain different chemicals/oils and some nits become immune. And treat at shorter intervals than recommended.
I found the old conditioner and comb method works great so keep that up. Also spray tea tree in their hair so they don’t keep passing it around to each other (I just put the tea tree oil in a spray on conditioner bottle).