12 PCS Colorable Drawstring Backpack for kids with 12 stackable crayons (7 Colors Each), Perfect for return gifts, birthday goodie bags and art party favor bags for kids

Maybe something like this? https://www.amazon.com/dp/B0DDXM9MRH/ref=sspa_mw_detail_1?ie=UTF8&psc=1&sp_csd=d2lkZ2V0TmFtZT1zcF9waG9uZV9kZXRhaWw I don't know if this particular brand is good but essentially you can get any kind of white tote bag (maybe with a colouring page design on it or maybe a design featuring a family motto you make yourself and get printed). Then you can colour it in together with fabric markers/fabric paints. The smaller children might need help (with fabric paints for example you can do simple hand prints or hand print animals) but the older ones might like something like this