Word Puzzle Challenge - Help me with my homework

Ok, if DD and I have to be challenged so do you. She is working on her Language Arts homework . She has to create a puzzle where each word builds on the next. The letters have to stay in the same order, but you can one letter at a time anywhere in the word. You start with a two letter word and pyramid up to an eight letter word.

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WARNING: This is much harder than it first appears.