Very exciting!! And yes, some mares will let the stallion breed then even when they are pregnant, so if she was still with him, it's quite possible she took on the first cycle, and then let him breed her again.
VERY NICE babies she produces!! The Foal Time Strips are wonderful, and they will let us know when she's ready if she tries being sneaky and not give us all the previous signs she's given. And remember, we're only as far away as a phone call if you need immediate help. My number is: 863-990-3210 and I'm always up and ready during foaling time -- no matter what the hour! And if you have cameras, all the better!