moderate hind limb flexural laxity

Hi dr. O.
I am interested in buying a filly who is about one week old. She was born with moderate laxity in the hind limbs, yet the condition seems to be self-resorbing every day a bit more. I would like to know if this can affect the horse’s future athletic potential for higher level work, even if it completely self-resolves within a few weeks? Is it a weakness that can cause other problems? It seems this mare has given a few foals born this way, is it genetic? thank you