Here is what Wikipedia says about Becky Thatcher:
Becky is Judge Thatcher’s daughter, known for being Tom Sawyer‘s love interest. Her long blonde hair is always worn in braids. She wins Tom’s love from the first moment he sees her. When she first encounters Tom, she gives him a purple pansy to show her love. She soon becomes “engaged” to him by swearing to love only him and sealing their engagement with a kiss. When he mentions that he used to be with Amy Lawrence, Becky believes he still loves Amy and gets angry at him. Tom wins her back by telling a lie and takes the whipping for the breaking of their teacher’s anatoy book, which she accidentally rips. In Huckleberry Finn she is also referred to as “Bessie”. Becky was based on Laura Hawkins, an actual friend of Samuel Clemens.