If one has the opportunity to attend either a Brit Milah or a shiva house (but not both), which is preferable?

Going to Minachim Avel, a Shiva house is a great Mitzvah, it is included in the Mitzvah of "Ve'ahavta Le're'acha kamocha", loving a fellow Jew as you love yourself ("The Chafetz Chaim" in his book "Ahavt Chesed"). However attending a Brit Milah ceremony is not a Mitzvah by itself (Except of the Mitzvah of "Gmilut Chasadim' by making someone happy). I think you should go to the Shiva house. May we hear only of Smachot. Rabbi Yitzchak Grinblat