Best: JFDI (travel, that is). Tho I think I gave it to myself.
Worst: Sure, take an 18mth old on flights in Y straight through to LHR. And if that isn't fun enough, don't pack spare clothes for yourself in-flight. Oh, and then to make it more fun, try to put toddler to sleep in coughpy EUR40/night cubby room and can't get her to sleep til after 10pm. Then wake up at 2am the next morning to go to an ANZAC day Dawn service.
Oh hang on, not advice, just what we did. But I'd do it again, just not book that cheapo hotel with a toddler again.