Can we concat two properties together in binding expression? If possible without converter or without writing two textblocks and setting them individually?
Like alpha-mouse suggests MultiBinding won't work out of the box, but this guy has thrown something together that might help:
If that seems a bit rogue, then maybe try putting a combined value property on your object as a helper for the Binding mechanism, like:
public string FullName {
get { return this.FirstName + " " + this.LastName; }
}