I read this book in middle school, 1995. so book is late 80s-90s. Three siblings, 2 girls and a boy, with the boy as the middle child. the youngest sister is ill/sick/crippled in some way. home life is not awesome, and they may or may not have moved to a new house- a huge tree in the backyard, they each find different items in the “new” backyard and decide to bake all of them into bread that mom or grandma was making. i think one of the items was a wire in shape of a crown, and another thing for the heart and something in the dough mans hand. this became some kind of magical talisman that made the little sister stronger and or able to perform magic. i also distinctly remember (i may be wrong) them having an entity i thought was rowan or something with an “R” that they worshipped for giving them this magic, and it became mad for some reason, resulting in the little sister climbing the tree to give back the dough man, and her falling…