Answer:
The word "indiscreetly" is defined as lacking prudence, good judgment, or circumspection". This paragraph provides the context to answer this word in the line "(...)the doctor met his fate while indiscreetly playing with a dangerous pet". You show lack of prudence or good jugment if you play with a dangerous pet.
I think if I understand this correctly, you're sentence should be "My mom was so proud of me"
"So for me the world became beautiful." I believe that would be your answer.
