I discovered that with some colored paper, water in her cup holder and a paint brush the baby can have a great time "painting" along with the big kids. Sometimes she uses brush and sometimes fingers but she always loves to play in water so this was just the thing.
Play-doh has been in use a lot recently. All three have been enjoying it in someway, the baby likes the tool and getting them out of the bucket. Also she discovered that the bucket makes a great walking assistant.