design opportunities

hi there, i am a 3d (product/furniture)design student based in cornwall. i am currently working on my final major project. i am interested in designing a product/ piece of furniture for growing children. my course is concerned with sustainability and for this project i am particularly interested in designing something for children that can adapt as the child grows and develops. the aim is to produce a product with a longer lifespan, reducing wastage and the need to replace it after the child grows out of it. i would also like to design something that really connects with the user, so be interactive in some way, to develop an emotional attachment and encourage creative input from the child (eg lego).
i am at the research stage of my project and i have come here looking for insight from parents into what children need/want when growing up. if anyone has anytime to give me feeback on the following questions i would be incredibly grateful!

what do children need(cot, high chair etc) when growing up and at what stage of life do they need it?

what are the biggest challenges children face when growing up? eg learning to walk

are there any products/pieces of furniture that you find yourself constantly needing to change and replace as as your child has grown out of them?

are there any products that you find have a particularly long lifespan within your childs development- perhaps because your child grows attached to it?

have you noticed any areas in your childs life or yours where there might be a design opportunity that could help/improve the life of parent or child(or both)

any help by way of response or feedback would be greatly appreciated and could really help me develop a successful product, thankyou, alex