Is it normal for a 15-month-old Boxer to not have had her first heat?

Typically dogs do have a heat every six months, but it could be Cleo had a heat and it was a silent heat. Silent heats are when the dog shows no outward signs of being in heat. You can have her checked out by a vet to be safe. Best of luck.

They will never ne as large as their brother being female. Sometimes the first heat can be silent in that you dont see any outward sign. I would keep a close eye now as their second heat should be imminent.

I'm wondering if you mean that Belle has an underbite. This can be common in breeds such as the Shih Tzu. As for not being in heat yet, she can go into heat anytime, so I would not worry about her being nine months and not having a heat yet. It can take up to a year of age before she goes into heat. I wouldn't be worried that there is a problem with her reproductive system. Best of luck, I hope this helps!

It can take up to 12 months or longer for a large breed dog to go into heat for the first time, so Eos may not be mature enough yet. I am concerned that she bled all over your bed two weeks ago and I am curious as to what could cause it, but if it hasn't happened since, maybe she injured herself causing the bleeding. I would wait a bit longer to see if she goes into heat.

She could still go into heat at any time. Some dogs go into heat later than others, although smaller breed dogs tend to go into heat by a year of age. It could also be that she has gone into heat, but it was a silent heat so you didn't notice any signs of it. I'd have her checked out by a vet to be safe. Best of luck.

Normally, bitches in season do not behave very differently from their usual selves. Since it is her first heat, there may be a problem showing up that was not evident before her reproductive organs became active. Or, it could be something else altogether. Your best bet is to take her to the vet for a thorough exam to determine an accurate diagnosis and, if necessary, appropriate treatment plan.

Yes, it can be normal. Often times though, they have gone into heat, you just didn't notice. Some dogs keep their vulva clean so you don't notice any bleeding. If you are worried then I suggest you take her to your vet for a breeding soundness examination.