Suggestions by @user_284573

Violet McGraw

as Lucy Lamb in My Fan Casting for The Family Upstairs(story removed)

Score: +1

Evan Peters

as Miller Roe in My Fan Casting for The Family Upstairs(story removed)

Score: +1

Emily Alyn Lind

as Libby Jones (Serenity Lamb) in My Fan Casting for The Family Upstairs(story removed)

Score: +1

Keira Knightley

as Grown up Lucy in My Fan Casting for The Family Upstairs(story removed)

Score: +1