A/N: I saw a headcanon that had a trans Wilbur going back in time, becoming Franny, and being her own mom.
This is not that, but I liked the idea of a trans Wilbur anyway, so here.
"Um... Dad?"
She stared down at the floor, stomach churning with nerves. "I... I wanna tell you something," she said softly.
Her dad looked up from his current invention, and, sensing her nerves, set it to the side. "What is it, Wilbur?"
She flinched with the use of her birth name. "I... I think I'm trans," she mumbled. "Can you maybe... Call me Willow? And with, you know, feminine pronouns?"
He smiled as gently as he could, attempting to comfort her. "Of course," he said. "Have you told anyone else?"
"I'm going to go tell Mom," she mumbled. "But no one else. Not yet."
"Alright. If that's all you needed, Willow, I should get back to work."
A smile tugged at her lips when he so easily referred to her as her new, preferred name. "Do you need any help?" she asked, clearly nervous about talking to her mother.
"Willow..."
She pouted, despite the joy that came once again. "Okay, I'll go talk to her... Wish me luck."
She left, heading down to her mother's music room. She hesitated before entering, watching, listening to the music. Stalling.
"Wilbur?" her mom said, stopping the music. "What's wrong, dear? You look sick..."
She swallowed thickly. "I think I'm trans," she choked out, finding it so much easier the second time. "C-can you call me Willow and use feminine pronouns? Please?"
Her mom smiled, relaxing. "Of course! Oh, goodness, I thought something was seriously wrong! Does anyone else know?"
"Dad does. But no one else yet."
"Well, when they do, we'll go get you some new clothes. Maybe use that hair-growth stuff your dad's been working on and give you a new hairstyle..." Her mom went on and on, and Willow relaxed, smiling.
She hadn't had a reason to be worried.