Pieces for 4 and 6 hands (one piano)

[fuzzy1]

My children are piano students, and now during COVID times we find that we have a lot more time to practice together. The older two learned a Haydn minuet for 4 hands to play together and it sounds lovely. So, looking for more pieces:

1. For 4 hands for the two older children (12 and 10 years old). The 12 year old is quite proficient, about level 6-7 ABRSM (currently plays Bach 3-part inventions, Brahms waltzes, Mendelssohn Songs without words, and Chopin preludes/waltzes). The 10 year old is a late beginner / early intermediate, about level 4 ABRSM (currently plays Schumann album for the young, Bach easy preludes). Ideally the pieces would have interesting parts for both and not just melody vs accompaniment.

2. For 4 hands for the middle and youngest child, these would be very beginner pieces as youngest child is just starting (6 months of lessons).

3. Is there such a thing as pieces for 6 hands, one piano, that all three children could play together? This would be very interesting for our family.

Thank you so much in advance!