• Evidence
  • Two years ago, an anonymous person started sending Dr. Ogawa boxes full of toys, along with some cash, on the first day of each month. And once every year on a winter, Morning Glory flowers get delivered to the hospital where he worked.
  • Dr. Ogawa received the flowers on that exact same day. However, this time the money came separately with a letter.
  • Coincidentally, as Conan was playing with one of the toys, he discovered that there was a username in the video game that was not of Dr. Ogawa's five-year old son, Yuta. He rummaged through patient records and found that Tomoya Ogino, indeed, was a kid who passed away three years ago on that day after being operated on by the doctor.

• Conclusion

Conan deduced that the presents were not given to Dr. Ogawa in gratitude, but with grudge and hate, by someone related to Tomoya Ogino.

Sensing that Yuta was in danger, they rushed and found him in a park near his kindergarten with an unknown man. Turned out, this man was Tomoya's father, who planned to end Yuta's life on the same day and at the same age that Tomoya died. The father lured Dr. Ogawa and Yuta with his son's old toys and life insurance money, and sent his son's favorite flower to commemorate his death.

Had Conan not interfered by kicking a nearby soccer ball towards the man, Yuta wouldn't have been saved from an ill fate.

As for Ran, she stopped her suspicion that Conan was Shinichi. He had asked Dr. Agasa to call Ran as him using the Voice-Changing Bowtie.

• Motive

Tomoya's father could not accept that Tomoya died not of surgical complications from Dr. Ogawa's hands. He blamed Dr. Ogawa and planned to have his revenge by taking away what he believed was also taken from him: a father's son.