We bought two calves on the 6th of August. They are roughly about the same age, one 12 weeks old and the other 10, but I'm concerned about the younger one, he doesn't seem to be growing as much as the other. I can tell that the one has really grown in height and weight, but as for my little fellow, I don't see it as much. They are both grazing throughout the day and at night the little one gets a bottle and they both get feed. I've weaned the older one as he is doing well and gaining weight like crazy! The little one grunts alot I'm not sure if that's normal? When I go to pet him or brush him, or when he eats feed is when he does it. They were about the same height but now the difference is very noticeable. Is there anything I should be concerned about?