Let me tell you a story.
Once upon a time, there was a woman who had a horrible man for a husband. He didn't hit her, but he was loud and loved to put her down with his words. They had a son named Jonathan who was the bright spot in the woman's life, since he seemed to understand that his parents weren't in the best place but consistently sided with his mother. The woman was even planning to leave her husband, but that changed when she found out she was pregnant again. Her husband found out before she could try and hide it and she was stuck with no way out. Her only solace was a police officer who happened to be her closest friend. He stood by her through her pregnancy, often taking care of Jonathan while she was at check-ups.
Then she found out she was having twins.
One boy, and one girl.
She knew that her husband would neglect the twins as much as her other son. And she knew that she wanted at least one of her children to have a better life. So she and the police officer came up with a plan. She would keep the boy, and he would take the girl to raise as his daughter. Her husband didn't know that she was having twins, so the lie would be easy to tell. And he didn't suspect a thing. He wasn't the smartest man and she was wondering how she'd ever loved him enough to marry him in the first place.
When she was close to giving birth, her friend brought her to the city where nobody knew her or her husband. She went into labor and was brought to the hospital, where her son was born first, then her daughter. She named her son William James and her daughter Jane Eleanor. They were both so perfect and beautiful, and she wished that she could raise them both. But her friend promised that he'd send her pictures and letters to make it easier. And so she let go.
As she predicted, her husband was no less caring towards Will than he was towards Jonathan. She was glad Jane (or El, as her friend had nicknamed her after her middle name) was with the police officer in Chicago. As the letters and photos arrived, she monitored her daughter's progress as much as her son's. Jonathan and Will had no clue they had a sister. One day, maybe they'd meet her. And they'd be mad at their mother for lying and hiding her. But for now, all she could think of was that her family was safe and well.
Especially once she divorced Lonnie.
But that wasn't the end of the story…
No, because the truth would come out. And her sons would be mad at her for lying. But they'd be overjoyed to have a sister, and El would be overjoyed to have brothers. And Hawkins would see the closest set of siblings that it had seen in many, many years. But it would also see an epic story of young love, of sibling rivalry, of learning to let go and move forward. It would see friendships tested and tried, emerging stronger or more broken than ever, new ones emerging from the ashes.
And it all started with Joyce Byers' lie to Lonnie.