I have a 4 week 3 day old pup bullmastiff x pit bull (only one mum didn’t get a chance to kill) and had a litter of 11 Staffy x pit bulls that are 5 weeks old had two pups over night die on separate night one after the other now tonight being to paranoid to sleep with 10 healthy pups scared they going die when I witnessed the lone puppy that at birth grew up with her sisters pups kill her litter mate same as always it was always the smallest one (she’s the biggest pup there is apart from the first born male out of her older sister litter) heard a puppy struggling got my phone turned my torch on just as I seen this pup over him by the throat picked him up and shook him all within seconds of glancing over it is possible so to the skeptics saying it’s hard to believe I’m sorry but I witnessed this and wished I didn’t so it does happen unfortunately