The pattern is available on Payhip and on LoveCrafts

As of 24 June 2020 the pattern isn’t available on Ravelry.

These stranded socks are knit from the cuff down and incorporate a heel flap with a small checkerboard gusset.
Two ponies are shown on the center of each leg, one in the front and one in the back.

The pattern contains three sizes:
S = EUR 24; US Kid’s Size 7
M = EUR 28; US Kid’s Size 10
L = EUR 32; US Kid’s Size 13

Since kids grow fast, instructions for lengthening the socks are included.

An adult’s version of the socks is available: Lady Farrier.
Get both patterns for 5 Euros. No coupon code needed.