A reported height range for Shepadoodles stretching as low as 13 inches strongly suggests what about the parentage in those specific litters?
Answer
The inclusion of Miniature Poodles in those specific litters.
A low height of 13 inches is far below the typical range derived from Standard Poodles or German Shepherds, indicating that the smaller Miniature Poodle variety was likely used in the cross for those specific puppies.

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