Mum pairing is son?

I had a breeding pair and the dad got unwell and died. I've had loads of fry from that pair and wasn't to fussed that I lost that pair. 

Anyway I put the female in my show tank and within a week she's paird up with her son. Do I Pull th both out and give them a go on breeding or will the fry be affected? 

Thanks jay.

Hi Jay,
Breeding sibling to sibling, or parent to offspring will result in a degree of inbreeding in the offspring. Excessive inbreeding can result in weak offspring, reduced fertility and and an increase in deformities. The question is what degree of inbreeding is "excessive". Some breeders refuse to contemplate matings involving that degree of inbreeding, whilst others are happy to carry on such pairings for several generations.
There are some positives in carrying out controlled programs of inbreeding, it can be used to "fix" desirable characteristics, and can be used to weed out deleterious (harmful or detrimental) genes.  
My personal view is that, in general, I aim to keep inbreeding below a coefficient of 12.5% (equivalent to mating 1/2 siblings, or Grandfather to granddaughter) unless I have a specific purpose in mind which can't easily be achieved without a closer pairing.
That said, although you're unlikely to encounter too many problems with a single parent x offspring mating, unless you have a strong reason for such a pairing, I'd be inclined to remove one or other of them and let the remaining one select a different mate!

Your answers to everything are always brilliant. This forum is lucky to have you  thanks mate.

thanks mate.

No problem, nice to be appreciated!