Corrected entry: When the gang is thinking about baby names, Esther is brought up. We then see Marshall and Barney at the strip club where Esther shoots out a bunch of playing cards and one sticks to Barney's forehead. He peels it off and says "That WAS my card!" But he never looked at the face of the card, so he couldn't possibly have known which card it was.
Corrected entry: In Baby Talk, Marshall's father gives him advice on how to conceive boys and avoid conceiving girls, because Marshall's parents had "all boys." However, in the Season 1 episode Belly Full of Turkey, Marshall's sister is a part of the family.
Correction: The character you're referencing is Ashley Eriksen, which would be Marshall's brother Marvin's wife, Marshall's sister in law.
Correction: He said this as a joke. Esther wasn't doing a magic trick and Barney never picked a card in the first place.
Bishop73