Husband wants to have sex while sleeping

Mi

Hi all, I have been with my husband for 8 years and every now and then, like maybe few times a year, we would be sleeping, and then at 1 am or so he wakes up with a huge appetite for having sex with me- if I reciprocate he fully wakes up and we make love but if i don’t (CAUSE I AM SLEEPING!!!???) he just sortof falls back asleep. Is this normal.. feels like he is posessed or something 😅