My cow was bred 5 months ago, has not shown any signs of heat since and is starting to get a big belly. She has always conceived the first AI, every time - so I have not been worried about whether or not she is pregnant. It seems obvious. She has an 11 month old heifer daughter and I STILL have to keep them separate or the baby will nurse. Ugh! That's a different problem. Last night and today, the mother has acted super interested in the heifer, bawling when not near her. Unfortunately, my son tethered them near enough to each other that the heifer nursed - ugh. Heifer is acting very sick to her stomach. When I went to walk them up to the barn today, the mother cow literally tried to mount her daughter. She has done that once before, back in Nov when she herself was in heat and I had her bred. Does this mean that she is NOT pregnant and has come into heat or that she is pregnant but is in heat anyway or could the heifer be in heat? Do pregnant cows mount cows that are in heat? I am beginning to think that the heifer is in heat. Her vulva looks red. Sorry - haven't had multiple cows before. BTW: Should I be worried about the heifer with a belly full of milk? She probably got a 2-3 quarts.