The mother has a horrible shoulder, a long back, and a gooserump. She isn't really butt high but she is still built pretty downhill (draw a line from stifle to elbow). She isn't breeding quality at all, and I'm surprised you got a baby to look like that. She's swaybacked, but that's okay because she's an ol' gal.
For sterling- I like her neck though it could be a little longer. Her shoulder is alright, looks like she has mutton withers. Her back is a little long, but if she's going to be a pleasure horse then that's alright. Little bit of a goose rump, but over all, not horrible.