Maybe now we have greater insight as to why Olivia broke up with him.
Or maybe you’re being trolled.
If there is a Notmybaby, claimed is the key word here. Think he would do that to his own flesh and blood? No. He will care for his stepson to the extent that most men who marry women with kids from previous relationships do. But given that SH threw a spanner in his career and blackmailed him into legitimizing her kid? He’s going to resent it, any man in his shoes would. That explains the odd distancing in his language and his overall behavior.