How to sum multiple op-amp outputs in Simulink?

I want to simulate state variable filter using block digrams.

Instead of using a sum block that sums two signal at a time, is there way to sum mulitple inputs from the gain output?

See image below, the bottom left gain output only shows a dotted line when I try to add it to the sum block.

Instead of using a sum block for every two inputs like the right side, is there a bette way of adding all the inputs?

Thanks