I live in Alexandria, VA, work in Landover, MD. Stay away from DC's south-east (and MD's immediate vacinity - PG County). Other areas around DC are fine.
DC politics, very liberal, of course. DC has a lot to keep the younger generations busy/ occupied/ entertained. But it's expensive to live in the city. Driving in DC is also aggrevating. Metro is the only way to travel there and keep the blood pressure down. Working for FedGov, your young'un will most likely get a Metro pass issued, so the commute will be free.
That gub'mint paycheck will also mean that housing should be affordable (maybe/ maybe not in the ciity, but out in the 'burbs).
MD, north and north-west of DC are nice. Politics in these areas have a slight right slant, but are outnummbered by the denser populations of leftists in the eastern part of the state. You do have all the ammenities you could want. But, it's still MD. Gun laws are awful. Ever changing taxes (that you only find out about when you file).
Northern VA politics is pretty centered. Slips back and forth between the left and right (more to the left, right now). VA, west of DC - Tyson, Vienna... - is REALLY pretty and expensive (still not as bad as living in DC, though). VA, south of DC (my area) is nice. A lot more affordable - unless you go south of Woodbridge, VA (then prices drop dramatically). VA's gun laws are great. Open carry (permit only issued for concealed carry, and it's easy to get).
Rush hour traffic, anywhere around DC, can be downright ugly. But usually it's just inconvenient. My 21 mile ride to work takes an average of 40 minutes.