Changing diapers during the night

Sa

I’m feeling a little bit of Mom guilt today since my baby has a diaper rash. He just started sleeping long stretches during the night and I’ve been so thankful for it. Before I was only getting about 2 hours of sleep at a time and now he sleeps up to 6-7 hour stretch during the night. I was encouraged to just let him sleep and change his diaper when he wakes up to eat. In the past he only slept for 2-3 hours so he got his diaper changed every 2-3 hours even during the night. But now I let him go last night 7 hours since he slept that long. I didn’t think he pooped since he normally wakes up and I can hear him grunting if he’s pooping. In that case I change him but last night I didn’t wake up to that so I changed him about 6 am and he had a little bit of poop in his diaper. Now i notice he is red down there so I’ve been using desitin today and feeling a little guilty for not waking to change him. Do you wake your sleeping baby throughout the night to change or should I keep letting him sleep like he does? I don’t want him to have diaper rash but I also don’t want to disturb sleep either.