1. It should be understood that animals can be trained to rape humans. totalitarian countries like Bolivia and Venezuela actually trained dogs to rape human females as a form of torture. At Dacheau documents exist that Nazis also did things like this

2. The small red tip of a dogs penis is NOT their penis–it is part of the head. Even on small dogs the penis grows to a length of about 8 to 9 inches long and will become engorged to the size of a man’s wrist–it does this to “lock” down on the female to ensure that once implanted, they cannot be dislodged before coitus is finished. This trait is also why being raped by a dog would be excruciating for a human

3. Once a male dog enters the orifice, that swelling begins–this is why dogs often get hung up–even if they want to retreat, they cannot. this dog in the story may have wanted to disengage but until ejaculation and the penis went down in size–he would be as stuck in the baby as he would in a human female.

Finally if this is the first case of a dog raping a human without training, I am more inclined to believe the parent or caregiver (or someone else)put the dog up to it, than the dog thought of it himself. Dogs like other animals reacts to its own species hormones to begin sexual engagement. When dogs are trained to attack humans–normally some human has trained them to do so. dogs are generally uninterested in humans for sex though they may eat underwear or lick sheets with emissions due to the protein level in that. Better keep an eye on this family–sometimes there is more to a story than meets the eye.