As many have responded, this is not unusual. But I can recommend something to help with her behavior towards him (and others). Look into Pheremones for cats. Products like Feliway and others are pricey BUT you don't have to see a vet for a RX or try to shove pills down their throat, so I think of them as VERY AFFORDABLE. These pheremones are synthetically made to mimic those that cats rub on you when they push their cheeks/face on you (or their surroundings). It helps the cats feel safe, wanted, and friendly. My understanding is that they now come in colars, sprays, and diffusers. PM me for more details.