Mom in heat, her son is here with us also

Question
I have my daughters 4 year old female yellow lab, she started her cycle yesterday, Her 11 month old male son is also here with me and has not yet been altered.  When do I need to start keeping them apart, and for how long, to be on the safe side?   Thanks for your help

Answer
To be safe, separate them at the end of the first week and keep them separated until the end of the third week.

The second and third weeks are when the most risk of accidental breeding is. Don't take this lightly. She will do anything to get loose and get to a male. Once loose, an accidental breeding and an unwanted litter is far from the worst that can happen. Such breedings can also result in fatal infections. She can get killed when she dashes heedlessly across the road in front of a car. Other dogs or coyotes may kill her.

You can expect the same thing about every 6 months for the rest of her life if you don't go ahead and get her spayed. There is no other answer, and no good reason not to. Besides saving the hassles, it reduces the chances of cancer later in life. Please make life easier for yourself, her, and society in general by getting her spayed as soon as a vet will do it.  I find it disappointing that anybody would both fail to spay/neuter their dogs and fail to learn such basics.