You have to buy it from the store,then once you've bought it,you have to make one of your sims go to the stove.then,scroll down to birthday cake.were it usually says 5LP,it will have an inventory sign with how many cakes you bought.click on the cake.your sim will start baking,and in one days time,you'll have a birthday cake for your baby/toddler!!happy growing!hope this helped, :thumbsup
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