My daughter-in-law is from STL, so she and son and grandchildren live there. Agreement was that the kids would be Redskin fans and Caps fans, but Cardinal fans also. My son has become a Nats fan...he grew up with the Gibbs Redskins and Langway Caps, but had no special interest in MLB. Now he does.
(And I left a couple of Curly-W hats for the kids. Unfortunately, the 6 year old sleeps under a Cardinals blanket. That's going to be tough.)