Why does Gwyndolin have tentacles?

Just always found this odd.

Gwyn, Gwynevere look completely normal.

So is there a different mother for Gwyndolin? If so, who? And who is Gwyn's consort? Does it say anywhere?

Really didn't think about it very much, as most video games really don't do a good job of explaining things in a way that makes sense, but I feel more thought and care was put into this game so there may be an answer.

If not, theories are always entertaining as well.

Snake...SNAKKKKKKEEEESSSSSSSS.

GWYN *** THE HYDRA AAAAAHAHAHAHAHAAHAHAHAHAHAHAHAAHAHAHAHAHAHAAHAH

Those aren't tentacles. Gwyn raised him as a girl because he was *ahem* jealous....