Toddler frequently waking up

We co-sleep with our toddler as she needs lots of cuddles and we’re fine with that. However, there are periods where she wakes up at night, sometimes 2-4 times, crying. We’ve tried just cuddling back to sleep, singing her favorite song, even asking if something hurts or she had a bad dream. But it seems like the crying and screaming increases when we are gentle and she response more by being very firm. She’ll stop waking up as much and even sleep through. She does remember what happens because she’ll tell me the next day. We have no idea why this is happening, sure she’ll have a bad dream but on occasion is every night. Any ideas?