How can I run a process and then immediately get the maximum amount of memory the process and any processes it spawned used once they exited?

So as the title says really I wish to run a command or pipe some commands together that will then print out the total RAM used by the process and anything else it spawned (so basically the total RAM used by the process tree I suppose).

I've googled this and it seems that its a really hacky mix of time and valgrind but I was hoping there was something else I could use?