def find_children(words, word):
    """Find all children of a word, i.e. words that are revealed
    by dropping a single letter.
    words: dictionary of words
    word: string
    """
    children = []
    for i in range(len(word)):
        possible_child = word[:i] + word[i+1:]
        if possible_child in words:
            children.append(possible_child)
    return children