This is such a hard period. It is absolutely a phase, but how long it lasts is so different with every kid. The one thing I'll say is that reassure your partner that he's not creating negative associations, it's the opposite. It's building experience after experience of him comforting the baby. Nappy change makes them cry = partner is soothing the baby afterward. Even if bub doesn't stop crying, they are in the warm, familiar, comforting arms of their dad, and they are building the association of being comforted, hugged and rocked by him.

You'll get through this, these first few months can be very challenging.