I estimate that he is approximately 5–6 weeks old

Hello Doctor, I urgently need professional advice regarding my male kitten. I estimate that he is approximately 5–6 weeks old. I have two kittens of roughly the same age. When I first got them, both were doing very well. They were active, playful, eating properly, and gaining weight normally. However, one of them has recently started losing weight, and his condition is getting worse day by day. Weight history: - His previous weight was approximately 376 grams. - Last night, he weighed around 305 grams. - This morning, his weight was approximately 296 grams. He has therefore lost approximately 80 grams compared with his previous weight. Eating and drinking: He still has an appetite and can chew and swallow food. He eats boiled chicken breast quite well. I prepare it by boiling plain chicken breast in water for approximately 30–40 minutes, without adding salt, onion, garlic, or any other ingredients. I also offer him kitten food, sometimes mixed with kitten milk formula. He drinks water as well, and I have occasionally given him small amounts of water using a syringe. However, despite continuing to eat, he is losing weight. Changes in his behaviour and physical condition: - He sleeps much more than before. - He has become noticeably weaker. - He barely moves compared with how active he used to be. - His walking has become slower and weaker. He was walking normally last night, but now he appears noticeably less energetic. - He used to meow frequently, sometimes as if he were hungry or uncomfortable. - He has lost interest in playing with his sibling. Other observations: - His gums appear pink, not white. - His body and paws feel warm. - His ears feel somewhat colder than those of the other kitten. - I have not noticed any obvious difficulty chewing or swallowing. Comparison with the other kitten: The other kitten is doing very well. Both kittens have been offered the same food and feeding routine, but the other one continues to gain weight, remains active, and behaves normally. I am particularly worried because this kitten continues eating but is still losing weight and becoming weaker. Unfortunately, access to qualified veterinary care is very limited where I live in Afghanistan. I am looking for an experienced, licensed veterinarian who can help me understand what might be causing this. My questions: 1. What are the most likely causes of significant weight loss despite continued eating? 2. Could this be caused by intestinal parasites, an infection, a nutritional deficiency, anemia, or a digestive problem? 3. What examinations or tests should be performed urgently? 4. What can I safely do at home while arranging appropriate veterinary care? 5. Are there any warning signs that indicate an immediate life-threatening condition? I would greatly appreciate a professional assessment. I am very concerned about losing him, and I want to act as quickly and safely as possible. And I just realized blood comes while he poops Thank you for your time.