In Supernatural, John Winchester repeated Mary Campbell's worst fear. Sam and Dean also grew up as hunters. John traveled around the country hunting monsters bringing his sons with him. They were in and out of schools. Dean Winchester was brought in, while Sam Winchester was left in the dark about what his father really did. He wasn't left in the dark about monsters, though.

In episode 5 of The Winchesters, Mary (Meg Donnelly) is stabbed by a Djinn and put into a deep sleep. John (Drake Rodger) had to go into her mind to help her escape. To do this, Mary had to face her worst fear. This was being told at five years old that monsters were real and she would have to kill them. John ended up repeating this with Sam and Dean, despite helping her face her fear that day. Instead of telling his son, "don't be afraid of the dark," when Sam Winchester said he was afraid of the "thing in his closet," he gave him a gun. When Sam discusses this with Dean, Dean thinks that was the correct response from their father. He was all in on the family business from an early age. John was preparing his boys for what was out there. Sam resented his father greatly for how they grew up but eventually came to terms with his destiny.

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Did John Know Mary's Worst Fear In Supernatural?

Jeffrey Dean Morgan in Supernatural

It has yet to be revealed how The Winchesters is connected to the original show, so John may not have known that this was Mary's worst fear. These Winchesters could be in a different universe from the Sam and Dean fans watched. Mary and John could also have had a mind wipe, meaning John wouldn't have remembered.

If he did know Mary's fear, it was probably the grief of losing his wife that made him forget. So much of John's hunting was driven by revenge, which is how most hunters get started, with someone they love being killed.

John Had A Better Reason Than Samuel

Mary Winchester burning in the Supernatural pilot

While Samuel Campbell didn't need to tell Mary about the family business that young, John was trying to protect his kids after Mary died. His worst fear at that point was that a monster would kill his kids. And even though, according to Supernatural lore, John didn't know Mary was a hunter, it's hard to escape that life without monsters trailing you — especially when the Campbells and Winchesters are legendary hunters.

Samuel didn't know it then, but he was scaring his little girl for life. Her whole life was planned out for her before she even knew what life was about. Plus, she was now scared of the dark because she knew things did go bump in the night. Parents are supposed to tell their kids there's nothing there or, at the very least, pretend to kill them. Or, in this case, actually kill them.

John repeated Samuel's mistake. Regardless of the reason, Mary would not have wanted her boys to grow up hunting. She wanted her kids to have a life. The one Mary tried to have. When Mary gets resurrected in the later seasons of Supernatural, she is proud of her boys, but she would have liked them to have a different life because once someone is in it, it's hard to get out.

More: When The Winchesters Takes Place Compared To Supernatural's Time Travel

The Winchesters continues Tuesday on The CW.