is there any non toxic, kid and pet friendly grass/weed killer on the market? I have a problem with grass in my gravel walkway?

The best way to kill anything that is growing in a gravel walkway is to disturb the ph balance to create an environment where nothing can or will grow. You can easily do this one of two ways:

1 gallon white cider vinegar and 1oz dawn dish soap

1 gallon white vinegar 1 cup of salt

It is best to soak the weeds/grass on a sunny day for the best effects. You will notice the weeds wilting and turning brown within hours of the sun beating down on them. If you treat your driveway once a week, you will create an environment in the gravel that will help with disallowing seed germination, so whatever does grow will be easy to treat with additional applications of the solution. Do not use the sprayer on windy days as the solution will kill what it comes in contact with. I usually use a piece of cardboard to shield the boarder of my driveway and lawn to prevent over spray from effecting my lawn.

I use my teakettle. Pour boiling water on the weeds coming up through gravel. About as non-toxic as you can get. Pretty damn cheap, too.

It only works in places like gravel, since you wouldn't want to pour boiling water anywhere near plants you want to keep.

They wilt quick, and are dead the next day.

Make your own. White vinegar with a couple drops of dish soap in a spray bottle and spray the unwanted grass liberally.

Just don't spray it on anything you want to keep, it'll kill pretty much all plants.

The common Glyphosate-based weed killers will kill grass (and just about anything else with green leaves).

They are generally considered safe as long as you leave them long enough to dry completely before allowing kid & pets back in to the area.

Or, something like this?

https://www.amazon.com/Garden-Weasel-AG-Crabgrass-...

Or this - anything that affect the roots rather than needing to be absorbed by foliage can simply be applied then the gravel sprayed over with water to flush the stuff into the ground, where kids cannot get to it.

https://www.ortho.com/en-us/products/weed-control/...

Or a DIY mix - vinegar plus a bit of salt and detergent. Probably not a great regrowth-preventer but certainly effective and safe..

They make a wand you can hook up to a propane tank and you can basically burn them off that would be the best way to do it probably

a non toxic killer? boiling water but you could use vegetation killer if you teach your kids to quit licking rocks

You're never going to find something to kill grass, people usually want it. The weed killer is specifically designed to kill weeds and leave grass alone