What Is The Best Children's Book You Own?

I posed this question through HARO last week and was pleasantly surprised with the number of great responses that I received.  But for a few exceptions, these titles were completely new to me; thereby making me even more excited about the results of my online experiment.

For sake of ease, I am going to list the suggestions below (along with the links to view each one) in the order they were received.  I will also try and provide a quick blurb about each, based on how it was described to me:

1. Tractor Mac - life on the farm during the mid-20th century
2. Everywhere Babies - great text for co-reading with your kids 
3. A Hole In The Bottom Of The Sea - how an underwater oil spill can affect the environment
4. The Big M (Series) - written by a kid for kids
5. The Lion In The Library - I'm assuming Beth was referring to Library Lion
6. The Bird Book - an avian alphabet primer
7. Ida Claire Teaches Us To Care - another environmental effort
8. The Very Hungry Caterpillar* - pretty sure you know this one, but see my review just in case
9. Pete The Cat (Series) - a cat that does a lot of stuff written by a guy named Erik
10. The Little Rose - bullying in the non-fauna world
11. Monsters On Machines - need I say more
12. Baby Danced The Polka - rhyming and rhythm and a baby
13. Ish - perfection isn't always perfect
14. Marvelous Mercer - special needs and tolerance
15. How Do I Love You? - let me stress the version linked is the one suggested
16. Monster Mama - another anti-bullying book with mom as the hero
17. My Counting Party - learn to count to 20 and customize the title to match your child's name
18. Big Smelly Bear - keeping your child clean
19. Are You A Horse? - so funny it made college kids laugh
20. Human Body Detectives (Series) - pretty self-explanatory
21. Sticky Icky Booger Bugs - explains cystic fibrosis to kids
22. The Monstore - sibling rivalry and monsters combine
23. OK 4 Me 2 Eat - food allergies explained
24. My Body is Just For Me - teaches children body boundaries 
25. Whoever You Are - diversity and worldviews
26. Chocolate Me! - diversity as explained by the one-and-only Taye Diggs
27. If You Hold A Seed - realizing dreams and how it all starts
28. The Big Orange Splot - nonconformity and individuality
29. Miss Pickerell (Series) - quirky old lady who teaches scientific facts (from the 1950s)
30. Mirror* - a book about diversity with great content but, IMHO, substandard design

To be clear, I have only seen the books that are *starred*.  The rest are completely taken on faith.  If the title is followed by the word 'series', it is because the submitter did not specify which one they liked most.

I'm not going to add much commentary beyond this, but let me just say how reinvigorating it can be to compile a collection of real people's favorites versus working off of a glorified checklist full of the same old names!  If I had to pick a few that looked most interesting to me, they'd be: #13, #18, and #19.

PS:  Special thanks to everyone for all of your help!  See the comment thread for special shout-outs to neat people doing neat things (or to add your own suggestions)!