1. left early
2. Den went shopping
3. Spring, Summer, Fall, and Winter (+1)
4. incredible
5. animal toys
6. add it twice (3rd letter)
7. position in the tranny
8. location near Hudson (2nd or 3rd letter)
9. Lake NE of Hot Springs
10. stuck in this place
11. fair ball, over the wall
12. slanted sunshine (2nd word, 3rd letter)
13. pixie tumbles

You can validate your puzzle solution with certitude.