Nightly leaks

My 6 month old baby is leaking through her diapers every night! It’s been happening for a week now.

This never happened with my son so I don’t know what to do.

I tried her in the next size up for diapers but she still wakes up wet 😕

She sleeps 12 hours a night and I’m scared to try to change her diaper in the middle of the night because I don’t want to wake her. Is there anything else I can try??