If this is in relation to wild cats of Britain (i.e. feral cats) as opposed to the wild "Bob" cats of North America, the queen tends to "nanny" her young for a relatively short period - often less than 4 months before they're expected to go out and fend for themselves. Responsible local authorities in the UK now have a speying policy regarding feral cats, as aside from their increasing number, the interbreeding between queens and their male offspring has shown a dramatic increase in kittens with severe birth defects.