So I'm making a wedding cake for next weekend, and it's gonna be tall. They are asking for my vanilla with a pastry cream filling. I'm worried that with the filling being soft, that it will compromise the stability of the cake. Any tips for using a filling like this on tall (5 tier) cakes would be great right now! Starting to panic and think it may be a bad idea!

The filling has nothing to do with the stability of the cake. Just make sure you pipe a dam around it.

Use the SPS system if you can, it will really help keep the cake stable. I've read that some folks add cake crumbs to a small batch of filling and use that to pipe a damn, so it's really thick. You could try that?

Just like the others said...a good damn to prevent the filling from sliding out. Also chill well before delivery so the cake can be nice and firm during the car drive

I always use some thick buttercream for my dams, and that works well for keeping the filling in the cake. I was just worried about the firmness and wether or not a soft filling would affect anything. I've never done a soft filling above two layers.