I bought my ducks at a Dodges grain store, there were about 40-50 mallards in the bin and I bought 8. Out of the 8 I have 6 left 2 males 4 females I tried hatching 3 eggs in an incubator and they were doing good but didn't hatch in the end. After reading a few posts here and seeing that ducks coming from the same parents wont have viable eggs or they could have problems. Is this true? and if so how likely would it be that my six all had the same parents coming from the same hatchery on the same day?