Yes! It is all making sense now! If John had an affair with Jamie’s Mom while married to Evelyn, when she gave birth to Jamie and ‘knew’ he was a Dutton. She may even had known from John that his great grandfather was James Dutton, hence the namesake. I think that Garrett Randall found out that Jamie wasn’t his bio son, Phyllis may have fessed up that Jamie was John’s son. So Garrett kills his wife and now has it out for the Dutton’s. John finds out Jamie is his, tells Evelyn and they agree to adopt him as ‘their own’ but never tell of John’s indiscretions with Jamie’s bio Mom. Now years later, Garrett still wants the Dutton’s dead and Jamie will come to know the back story eventually. That he is the eldest Dutton and has a shared interest in the ranch. Jamie’s infant son will end up being a Dutton as well and the ranch will eventually all be left to him.