Calf seems to be very small for her age?

Hello, my mother in law bought my fiance a polled hereford calf from a live stock auction June 18th of this year. She had just been pulled off her mother and they guessed her to be a month or so old. I dont feel like she's growing the way she should be. We have ran fecal and she did have some parasites but not many. My in laws said they almost think she's a miniature or just bad genetics. However, the steer she's with is also hardly grown I dont think. But he was a bottle baby. Here are pictures of them back in the summer and then recently ( one with their winter coat). Shes about 30 inches tall to her shoulders right now. If she was a month old in June she's about 6 months old now. Does this seem weird? She has had so many eye problems already she just had an ulcer in her eye a few weeks back. (Around the time the recent pick was taken) .