The mother:

Its father Sir Donnerhall, vice-champion at koerung 2003, winner of the test at Adelheidsdorf in 2005 with the record score of 163, German champion and runner-up in the world at age of 6, is one of the most appreciated stallion in Germany, father of the World Champion of the 5 years old Sa Coeur, then sold for 2,31 million euros at PSI auction. Sir Donnerhall is already father of more than 80 approved stallions including the champions Sir Nymphenburg, Silbermond, Sir Heinrich e Sir Schivago and more than 50 state awarded mares. Sierra descendes from a Hannover maternal line that has produced severals horses sold at Verden auctions and stallions such as Windwurf, San Carlos, Hermelin…

The father:

https://helgstranddressage.com/en/stallions/franklin/1469