Find the latest merge point of two branches

Question

Having two branches, how can I find the latest revision(s) where the two branches were merged? Is there a standard Mercurial command to do that?

This is the same as ques

Answer 1

hg log -r "children(ancestor(default, Cleanup)) and merge()" --template "{rev}\n"

is latest merge for default and Cleanup branches (polished version of Tim Henigan's answer).