My nephew and his wife recently had their second child, and they are following a well-worn path from the city to the suburbs.

Four years ago, childless and carless, they lived the urban life in the fashionable Washington, D.C., neighborhood of Cleveland Park. Child No. 1 pushed them four miles out, to the expensive inner Maryland suburb of Bethesda, where they bought a cozy two-bedroom condominium that had been converted from an apartment. Then, a couple of months ago, Child No. 2 pushed them another 12 miles farther out – beyond the Beltway – to Rockville, where they bought a four-bedroom, 2,200-square-foot house.

Now they are living the suburban life – which means, inevitably, a large yard, two or three cars, and an autobound life for all concerned, including their infant. Right?

Well, not exactly. Yes, Eric and Kate have headed for the suburbs. But their life isn't really very autobound at all. Suburbia to them means an end-unit townhome, one car, a daily bus trip to day care, a 10- to 15-minute walk to the library and shopping at Rockville Town Square, and D.C. Metro commutes (13 minutes for him, 30 for her) to work and back.

This is America's New Suburban Dream. In a lot of ways, it's just like the old one – the familiar scramble for a great school district, a lot of square footage, distance from urban grittiness, and proximity to schools, parks, and libraries. But in important ways it's different.

When they say they live close to the playground, they don't mean it's five blocks to a city park; they mean it's 30 feet from their barbeque, across the common area of the townhome development. When they say they've traded proximity for space, they don't mean they have to drive five miles to the store. They mean that by living 1,000 yards away from the Rockville Metro Stop – instead of 100 yards – they can get a four-bedroom townhome instead of a two-bedroom condominium.

It's not an urban life, exactly. Their townhome development – dating from the early 1980s – is not exactly a New Urbanist's dream. It's basically a cul-de-sac development bounded on two sides by strip shopping centers. The streets look a lot like parking lots and it's not all that easy to walk along the sidewalks in and of the development, as Eric and Kate often do. It's more Clarence Stein than Andres Duany. Clearly, it was designed to accommodate people expecting to drive to the Red Line station when it opened in 1984. Yet even with these drawbacks, it has an appealing combination of suburban feel and urban access.

And their life is not so urban that they've abandoned their car. The car is an essential component of life on most days – especially to shuttle the kids around, run weekend errands, and, of course, go on vacation. But Eric and Kate use the car differently. The trips are mostly short and it's possible to go a couple of days without using the car at all.

But that doesn't necessarily mean their life is devoid of the good things. A walk of about 15 minutes will take them to the center of Rockville – a surprisingly rich and urbane place and becoming more so all the time. Rockville is the county seat of Montgomery County – an affluent and politically liberal county of almost 1 million people – so there have long been tall office buildings in the downtown. More recently, the city, the county, and private developers – including Federal Realty – teamed up to transform a former in-town shopping mall into Rockville Town Square, a surprisingly dense downtown development project with a library, an "arts and innovation center," shops, and 6-story mixed-use buildings. Not surprisingly, the upper-floor condos aren't doing well at the moment, but the whole thing is walking distance from the Metro station – and from Eric and Kate's townhome. DuPont Circle or Cleveland Park it's not, but there's enough going on to keep most people – especially most family-oriented people – more than busy.

The walk from Rockville Town Center to the townhome is filled with close-up views of parking lots and strip centers along Maryland 355. This is exactly the kind of property that infill developers and planners salivate over as they think of multi-story mixed-use projects, which in turn terrifies most suburbanites, who fear ever-more-frightening traffic infestation. Amazingly enough for suburbanites, however, Eric and Kate don't seem to be afraid of more urban-style development creeping toward their townhome neighborhood.

Most smart growth evangelists would say that's because they understand the typical party line – that a walkable neighborhood works better as it gets denser, unlike an auto-oriented neighborhood, which breaks down because of traffic congestion when more development arrives. That's true enough – though it's kind of a nerdy way to put it. I'd guess Eric and Kate would think of it differently. To them, living in the suburbs revolves not around driving but around living. Though it's far from perfect, Rockville allows Eric and Kate and their kids to focus on living. Which, I think, has been the point of suburbs from the beginning.