Suggestions for a child room subject? My sister's moving out and me and my fiance are thinking about...

My sister's moving out and me and my fiance are thinking about area for a baby room. Anyone hold any ideas?
Can this vintage pushcart near some slight rust...
Answers:    Noah's Ark ,Fairy Tale characters that one is fun!! we bought adjectives kinds of fairytale books & displayed them within the room & we decorated 1 wall w/ different sayings out of respectively book & we bought different character stencils & matched them to respectively saying!!
Have Fun!!
Anyone tried a vinyl tile floor kitchen backsplash?
ducks or frogs