You didn't know how to tell Sam when you found out you were pregnant. After all, you two weren't committed. You both had feelings for one another and were sleeping together... but that was it. Neither of you wanted to commit because you were hunters. You didn't want the heartbreak if something happened to the other.

So, you didn't tell Sam. You kept it a secret. You would for now, at least. But, it wouldn't stay a secret for long. One hunt, you were with Sam and Dean, scouting the woods when you suddenly hunched over and started vomiting...