Stewart's Tree by Cathy Campbell

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Ellen's new baby brother Stewart has been 'lost'. Ellen looks in all the cupboards for Stewart, and even in the washing machine - then her family help her understand that Stewart has died and isn't going to come back. Together they plant a tree for Stewart, so they will always have a place to remember him.
A therapeutic children's book for explaining sibling loss to young children, colourfully illustrated to emphasise focusing on the happy memories of a lost child. The book ends with a guide to bereavement for children written by qualified clinicians.