We already know Ralph has some affinity due to his family name and/or heritage due to the Jim v Ralph debacle.
So let's look at this from Ralph's POV.
His firstborn son, with a last name that isn't Ralph. His firstborn son, with a first name Ralph, had no say in it and noticeably hates it. The same child he has yet to meet and will consciously and subconsciously be fed all kinds of negative information about his dad throughout childhood. If there is anything capable of penetrating his unwarranted guntly sized ego and into his wet brain, it's this.
Becoming 18 and questing to find Ethan is a bizarre fantasy that has no basis in reality. His first son is not going to recognize him as his father. Xander will be openly antagonistic to Ralph. The Ralph lineage ends here with disdain from the final descendent to his predecessor.
Could Ralph potentially fix this? Yes. The retard can simply fix things with Faith. He just can't get out of his own way... ever.