I originally didn't think Lily could be the character Ted is sad about, however with the additional information we've been given last week about Lily now having a daughter, that does add credence to the suggestion. I wonder if that was their intention? To delay the information about Lily being pregnant until after we've been hit with the "some female will die in the future" possibility? I don't think the Mother will be dead, because I don't think they would do that to Ted... it would really kill the replay value of the show. Lily on the other hand, while she's beloved, she's not the Mother. *Note: I have not and will not click the spoiler link above. At least not until the finale has aired.