Placing the baby files in C:\Program Files\EA GAMES\The Sims 2\TSData\Res\Catalog\Bins\EA Store worked for me, I am SO delighted to finally have these items, they've been making me sad since they came out and turned out to cost something like €5.

So thank you mistyk for sharing, thank you menaceman for altering the chair so that it makes noise and thank you maleucia for pointing me towards that other thread. I couldn't have enjoyed these items without you guys It is very much appreciated.