The Jonah birthday puzzle

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Across
  1. 3. Birthday boy likes to tell and laugh at these
  2. 4. Birthday boy's brother
  3. 5. Birthday boy is a fast ...
  4. 6. Oma of birthday boy
  5. 8. strong school subject of birthday boy
  6. 9. Special birthday guest
  7. 13. Father of birthday boy
  8. 14. Color hair of birthday boy
  9. 16. Instrument played by birthday boy
  10. 17. Teacher of the birthday boy
  11. 19. Birthday boy's sister
  12. 20. Birthday boy likes to play
Down
  1. 1. Age of the birthday boy
  2. 2. Mother of birthday boy
  3. 3. Boy whose birthday it is today
  4. 7. City which the birthday boy presented
  5. 10. Toy with nuts and bolts
  6. 11. Class of birthday boy
  7. 12. Bouncy sport played by the birthday boy
  8. 13. Favourite sport of the birthday boy
  9. 15. Favourite activity of the birthday boy
  10. 18. Beach where birthday boy likes to play with mates
  11. 20. Frequent flyer status of birthday boy