We've been doing this one with small children and it works pretty well.

Amazon.com https://www.amazon.com/dp/B08ML4XQNM?ref_=cm_sw_r_apann_ts_JBPGBJ935M1YX8RJ0Z8A

Each day is a different character in the advent story. There are activities as well, but we skip those since our kids are still too young.