If I have multiple cows using the same parents, (Example 2 water cows can potentially have blue slime children OR fruit juice children) can the collective BreedingChance for both child cows be over 100%?

So for the blue slime, 'BreedingChance' = 60
And the fruit juice cow, 'BreedingChance' = 75

So the total chance between the two equals 135.
Is it okay if it goes over 100? Or do the two Chances need to equal 100%? My friend who does a lot more of this stuff said above 100 might have issues, but I have no idea, I'm still pretty new to this.