Question

I am researching a statement a friend told me 4 or 5 years ago, that webbed toes or "twinny toes" were, historically, a sign of English royalty, or a sign (in England) that a child had "royal blood". Currently looking for any information to verify that.

Answer 1

Sorry, I can't tell you anything about that. If you find anything out, mind keeping me posted?

Answer 2

"Webbed toes" is the common name for syndactyly affecting the feet. It is characterised by the fusion of two or more digits of the feet. This is normal in many birds, such as ducks; amphibians, such as frogs; and mammals, such as kangaroos. In humans it is considered unusual, occurring in approximately one in 2,000 to 2,500 live births.

There are various levels of webbing, from partial to complete. For example, the rare Hose's Civet, a viverrid endemic to northern Borneo, has partially webbed feet. Most commonly the second and third toes are webbed or joined by skin and flexible tissue. This can reach either part way up or nearly all the way up the toe.
This condition is normally discovered at birth. If other symptoms are present, a specific syndrome may be indicated. Diagnosis of a specific syndrome is based on family history, medical history, and a physical exam. Webbed toes are also known as "twin toes," "duck toes," and "tiger toes."
The exact cause of the condition is unknown. In some cases, close family members may share this condition. In other cases, no other related persons have this condition. The scientific name for the condition is syndactyly, although this term covers both webbed fingers and webbed toes. Syndactyly occurs when apoptosis or programmed cell death during gestation is absent or incomplete. Webbed toes occur most commonly in the following circumstances:

Syndactyly or Familial Syndactyly
Down syndrome

It is also associated with a number of rare conditions, notably:

Aarskog–Scott syndrome
Acrocallosal syndrome
Apert's syndrome
Bardet-Biedl syndrome
Carpenter syndrome
Cornelia de Lange syndrome
Edwards syndrome
Jackson-Weiss syndrome
Fetal hydantoin syndrome
Miller syndrome
Pfeiffer syndrome
Smith-Lemli-Opitz syndrome
Timothy syndrome
Ectodermal Dysplasia