I am making a wedding cake that will be 4 layers size 12, 10 & 6
with pillars between the cakes. The bride wants strawberry filling. I need a recipe or I need to know where to buy the filling. I am also nervous about the fillings puffing out the sides of the cakes from the weight of the cake layers. Please help!

When filling a cake you use a dam of buttercream - rather thick; piped with a tip 12 - then fill w/jam or sleeved filling just below the level of the dam before adding the top layer of cake.
The weight of the cake layers should never be a factor as you must use some support. One can make teirs of 'cake' from jello when the proper support is used

There is a great and super easy filling recipe here on CC. I've not made it with strawberries, but have made the original version with raspberries. The recipe says you can use any frozen fruit (I don't use the lemon juice). It comes out thick and with the thickened buttercream dam (kakeladi) mentioned, I've never had a blowout. I dam and fill my cake and then let the cake settle over night in the fridge. I've used it for 3 different stacked cakes and people keep asking for it. It's called Raspberry Puree Filling and was posted by melysa.