I don’t think it’s the dog’s fault at all. The parents have to take responsibility for this.
But I easily see how this can happen.
A few years ago when my friends pit bull was younger, about 1-2 years old, this fuggin dog tried mounting my leg and humping it. Even worse, when i tried (quickly btw) to get him off, he held on tighter and acted like he was gonna bite me. I was like WTF. I had to basically fight this fuggin dog to the ground and hold him there until he calmed down. My friend said he did that all the time. I told him he needed to have his ballz chopped off, but I don’t think he ever did.
So I could easily see how a horny 2 year old pit-bull could own a toddler.