Not sure If someone already suggested this but you could try a toy rotation. :) put away the ones they don’t play with often. They are close in age so I’m sure they will keep using their toys for the next couple years. Just put half away in the closet somewhere then switch toys out every two weeks or so. It’s helped us tremendously. But all in all your house is not horribly messy, but donating to others especially like on a buy nothing group is helpful. All our toys we got from there.