Your male cat is fixed? It could be something about the hormones he senses with Riley and that will resolve itself once she is spayed....takes about 30 days for hormones to leave the system.
Will he eat on the other side of the screen for treats? If he associates Rylie with something special, it might change his thinking. Using the screen door is a great idea. How long have you been able to do this so far?
Ode to vanilla extract
This sometimes also works if you brush both cats with the same brush or rub the same piece of fabric on them. Scent swapping might also work.
Will he eat on the other side of the screen for treats? If he associates Rylie with something special, it might change his thinking. Using the screen door is a great idea. How long have you been able to do this so far?
Ode to vanilla extract
This sometimes also works if you brush both cats with the same brush or rub the same piece of fabric on them. Scent swapping might also work.