If you're getting kittens, get two to entertain each other. The possible issue with a kitten is you won't truly know their personality for a year or two, and they are bonkers/destructive as wolfie says. But also funny and very very cute.
If you just want one, I would get a young ish adult that you know is friendly - likes strokes, young enough to still be playful etc.
The rescue we got our cats and kittens from would rehome to a family like yours. I have found it's not as strict as dog rescues are for rehoming with children as long as they think the cat would be a good match for your circumstances. Some rescues like to rehome cats to homes where they have access to outdoors, others like indoor only, and some do a mix depending on the needs of the cat. So you would probably be asked about that in your screening questions.
We currently have 3 rescue cats - one that's 8 and very loving/cuddly friendly lap cat (we got her when she was around 2) and two 9 month old kittens - friendly in that you can stroke them and just about pick them up but they are far too busy to want to sit still for long - definitely not lap cats so far, that might develop in time maybe. They need lots of play. They make us laugh every day.
I agree with you that you shouldn't let cats roam near a busy road, so it's best to look for an indoor only cat or you could maybe look at cat proofing your garden or getting a catio if you want them to have safe outside time. There are facebook groups for this and there are companies that specialise in this - eg protect a pet. We've got a cat proofed outside space for ours.
Don't let this put you off, but do be aware that it can be hard having indoor only cats with kids that might leave a back door or something open. You'll need to think about the logistics of how to be sure they won't get out. You also need to make sure your windows don't open too wide and get either restrictors on them or something like a screen or 'flat cats' mesh so you can open your windows without the cats escaping.
Honestly, there are so many cats in the world already, rescues are struggling to find decent homes as it is, I would really say talk to a rescue first, they should be able to match a cat to you personality wise. Lots of cats are fine as indoor only - it depends on the cat, their personality and what they are used to. Some would be really unhappy as indoor only but many many cats are just fine with it, and have good lives. I don't think it is cruel to have an indoor only cat if it suits the cats personality and they are not already used to roaming outside. You will need to think about enrichment and toys though.
If you do get one from a breeder, make sure it's a reputable breeder. A kitten should ideally not leave it's mum before 12 weeks old. If you get a pair you might get away with slightly younger (ideally they should be with other cats until 12 weeks so they can get socialised). You want a kitten that's been vet checked, vaccinated, microchipped, flea treated and comes with a month free insurance. So no nasty surprises/heartbreak awaiting. You would also get these things with a rescue. And get your own insurance put in place straight away.
Good luck and enjoy!