It is possible for short-haired Corgis to give birth to long-haired Corgi babies. The hair characteristics of Corgis are determined by genes, and the combination of genes is random.

When short-haired Corgis breed, their offspring may inherit the short-haired gene , may also inherit the gene for long hair, or a combination of the two. Therefore, even if both parents are short-haired Corgis, their offspring may still have long-haired Corgis.

The length of hair does not only depend on genes, but may also be affected by other factors, such as environment, nutrition and individual differences. Some short-haired Corgis may have slightly longer hair as they grow, which does not necessarily mean they are long-haired Corgis.