ETA: I am not an AQHA member, but if someone is, they could look her up. I believe she is FQHA reg too.
Please do not jump on me for official AQHA colors as I do know that horses are not always correctly registered, but this is what AQHA has:
This mare here is registered as a dun.
Her two foals that I could find on allbreed are registered with AQHA as dun (by a dun sire) and a bay roan (by a bay roan sire) - that is not very helpful
If a horse has more than one color modifier (like roan, dun, cream, ...) AQHA will register only with one and maybe mention a second or third modifier in the description. This mare could be a dun roan, yet registered as a dun. Her sire is a grullo, her dam a bay roan. Why/where somebody came up with "buckskin" in allbreed - who knows.
Again - all this information is from AQHA and should be taken with a pinch of salt
I, personally, tend to call her a dun roan from the pictures.