If you have to leave her outside, then you need to get her fixed ASAP so your mom won't just have ONE dog she won't allow in the house, but and extra 12 puppies that need to also be in the house for a couple of months and all that involves.
My girls all behaved 100% normally when in heat. Just more licking to clean themselves up. I didn't notice any males around the yard, but that's probably because of the leash laws PLUS the fact I kept her indoors. My dogs did spot around the house so I'd see blood droplets on the floor (only at the start because I then put their panties on) but if your dog it only outside you'd miss seeing this.
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