The spin-off series Young Sheldon is being accused of ruining The Big Bang Theory's legacy to save itself. While the show has been attempting to distance itself from its parent project, it still features some voice cameos from the original cast. One major issue is how Young Sheldon portrays George, the father of the main character, as a hardworking man who is constantly berated by his family.
However, The Big Bang Theory showed him as a mostly drunk and neglectful father. To address this discrepancy, Young Sheldon is suggesting that George will cheat on his wife with his neighbor Brenda. It's important for the spin-off to stay true to Sheldon's traumatic experience of catching his dad's infidelity, which greatly influenced his habit of knocking three times before entering a room.