Crazy_DarkSide_Cat
It is something that I also thought and I imagine that the original author of Douluo did not think about that when making Xiao Wu, but logically Wiao Wu would not have that murky background of having hundreds of litters of children, the original author portrayed her as an innocent person so I imagine he would change the biology of the Douluo Continent rabbits to maintain that innocent image of Wiao Wu.