Harry A Cross is listed in the 1910 household of John A and Cora M Cross -- as their nephew. He is listed in 1910 in the Mary O Mertz household where John A and Cora M Cross are living as her grandson. That can only be if Cora's sister also married a Cross, but Cora didn't have a sister. So the answer to this apparent conflict, I think, is that the 1900 Census is more accurate and John A is not Cora's son -- though I am keeping him here in my database as such just to keep him visible in case more information becomes available.