Is There an Age Limit for Parental Imprinting?

Recently my daughter-in-law called to tell me our eight week old grandson had begun sleeping through the night. She added that her pediatrician indicated there is some speculation that infants adopt the sleep habits of their parents. My son, daughter-in-law and their older son all go to bed early and sleep well, so it makes sense that the new little guy will do the same. After all, what else is there to do when everyone else is in bed and the house is quiet?

The concept of imprinting is interesting. My own writing career has now expanded to include both sons in overlapping projects. Is it possible there is no age limit on parental imprinting? That's an unsettling thought. Or even worse, do imprinted traits lie dormant until some triggering event calls them out in one big family wave?