Hi Fitzchiv - a big warm welcome to you, Mrs Fitzchiv, Daisy and Frankie
It's always a thorny issue, the old "indoor/outdoor" debate, but there's no doubt about it that most cats love being able to access outdoor space, and once they get accustomed to it, it's a rare cat who will choose to remain an indoor only cat.
There are so many differing views on the subject, and all have valid points to be made. personally, I favoured keeping kitten cats indoors until around 6 months old, and then only permitting them to go out on strictly supervised outings, and before they'd had anything to eat, so it was easier to coax them back in. With our last 3 cats, that went completely out fo the window when my hubby began taking them on supervised strolls in the garden and the surrounds when they were still very much only babies - around the 3m onth mark. However, they weren't allowed out unsupervised until around 6 months old, and that was easier to enforce, as by that time the weather was beginning to change towards Autumn, and we'd installed a microchip reader catflap with a curfew option.
Fully understand your joint concerns about safety - we've lost two of our own cats to RTA's in the past year (both had free access to the outdoors) and one of our neighbours cats have been killed and one injured in the last four months. This has led to something of a division between me and OH - I would prefer to keep our remaining cats as garden cats and get our garden cat proofed.
However, this would incur a considerable amount of expense as it would inolve removing a conifer hedge around 7.5 feet tall (not cheap) and DIY/tree felling skills we dont have, OH wins the day with his belief that cats should be allowed freedom to roam, for whatever time is theirs for living.
You can get kittensoft collars (in a range of sizes) from Kittyboo collars (online) and they only do breakaway collars. However, always worthwhile reviewing the construction even of "safety collars" as some have been found to have faulty construction, which, if there is no keeper mechanism on the band, can result in the collar tightening instead of breaking if it gets snagged.
I think you may be in for some sleepless nights once your girls begin exploring, as there are bound to be fine evenings when they have so many absorbing things to investigate. If cat proofing your garden is a viable option, then you may want to think about doing it. There are various different methods and options available, whether doing it yourselves, or getting in an experienced installer.
Otherwise, I would keep up with the way you've begun - trying to allow them out with you there to keep an eye on them. Dont let them go too far at first. Leave the back door open, so they have a safe point of retreat. Think about getting a cat flap fitted if there isn't one there already, so the girls can gain access to the house without having to wait for you to return home - especially useful with winter coming on, and the potential perils of the weeks leading up to 5th November.
Cant recommend Sureflap microchip flaps highly enough - you can get different models, some with dualscan functions if you needed to ground one cat whilst giving the other free access, and another with a curfew function, so you can elect to keep your cats in within certain periods you choose yourself. Having said that, our cats managed perfectly well for years with just an ordinary flap, so it's a question of convenience and cost when it comes to choice.
Do you have any piccies of your girls? (hint hint!
)