Not really, when she had the kids she had the choice to double barrel or give them her surname. Lets not also forget that Sam has her dad's surname even though she never talks to him and used to abuse her mum, people put too much credence into surnames when really it's not a marker of good parentingAnd who can blame her? It’s like he’s excluding her
If the idiot keeps on having kids with him despite not being married, she's reinforcing bad behaviour.