sinful creatures.
Adam and Eve were sinless... until they committed sin. It was not necessary for them to do so, however.
Unfortunately, their sin caused the loss of grace in humanity and made people prone to sin... concupiscence.
Jesus and Mary were the new Adam and the new Eve. They were not born into sin and did not sin. It was through Jesus, with the cooperation of Mary, by her fiat to God, that salvation was brought to humanity.
Hail Mary, Conceived Without Sin
https://www.catholic.com/magazine/print-edition/hail-mary-conceived-without-sin
What the Early Church Believed: Mary’s Immaculate Nature
https://www.catholic.com/tract/mary-full-of-grace