Lynn had always been your best friend, out of 11 louds, you were basically the 13th (because Clyde was the hypothetical 12th child)
However, you had also started hanging out with Lincoln and Clyde. Lincoln started this more than a giant crush on you, and you didn't know how to feel about that. Lynn caught onto it and she was worried, she had always struggled with making friends, and now that she had one, she was so worried about losing you. She didn't mind you guys being mutuals, but the idea of Lincoln crushing on you? It made her scared and uncomfortable.
She just wanted to keep her friend, but it ran a little deeper than that... she loved you. More than a friend way, like a lover. She confided in her sisters, Lori, Leni, Luna, Luan, Lucy, Lisa, Lola, Lana, and even little Lilly. Like a group meeting, while you were outside with Lincoln.
Lynn had ZERO experience with love life. She was always sporty and aggressive, hyper, and sometimes she came off as rude but she never meant it that way. She was trying to do better at the friendship stuff and love life stuff but she needed help. She was lost and confused, so she desperately asked for her sister's guidance.