I first attempted one last March for my sis-in-law (again first baby - and a girl too!) as part of their baby one-month party. Chinese & Vietnamese culture celebrate a baby's one month birthday or Full Moon (滿月) as it's known in Chinese. It also marks the end of the mother's confinement period.
Here is the one I made for my friend---
It's constructed from Size 3 nappies for 9-20lb babies. I got them slightly bigger so she could enjoy the cake before dismantling it to use the goodies! It also has 3 muslin cloths (burp cloths), 7 baby vests and a pink fleece blanket all topped off with a soft cuddly giraffe!
It was finished by wrapping in cellophane and tying with curling ribbon. My friend loved it and doesn't intend on dismantling it to use anytime soon if she can help it! It's a bit wobbly looking in places - especially above the bottom tier. This can be strengthened by filling the gap at the top by using some rolled baby socks.
This was last year's creation - again another pink cake!