The changes in a dog's appearance are related to its growth and development process. Usually in its early childhood, the appearance characteristics have not yet been fully formed, and it may appear "ugly". However, there is no definite answer to the specific months when the dog is ugliest, because the appearance changes of different breeds of dogs vary greatly during their growth, and the individual differences of each dog will also lead to differences in appearance changes.

Generally speaking, within a few weeks to several months after birth, dogs undergo various changes in their bodies due to various changes in their bodies. The parts are developing rapidly, and the appearance may appear uncoordinated, such as sparse hair and unclear facial features. In addition, some breeds of dogs will go through a moulting period as they grow. The hair at this stage may appear messy, which will also affect the overall appearance.