I'm beginning to think I've got horses rather than Boxers! At 10 weeks, Chief was 18 lbs. Sarge, my other Boxer boy, was 13 pounds at 7 weeks. Chief just turned 5 months on Nov. 29 and he's already a whopping 45 lbs! Sarge turned 4 months on Nov. 20 and he's 39 lbs. The vet predicts that they'll both likely weigh in at around 80 pounds by the time they're done growing.