Bad babysitter: Wolverine
Cover of Uncanny X-Men #195 (July 1985), art by Bill Sienkiewicz and Dan Green
Worse babysitter: Kitty Pryde
Panels from Marvel Team-Up #135 (November 1983), script by Bill Mantlo, pencils by Ron Frenz, inks by Mike Esposito, colors by George Roussos, letters by Joe Rosen
Extremely inappropriate babysitters: Tarantula and Black Cat
Panel from Heroes for Hire v.2 #7 (April 2007), script by Justin Gray, Jimmy Palmiotti, and Zeb Wells, pencils by Al Rio, inks by Tom Palmer and Terry Pallot, colors by Brad Anderson, letters by Randy Gentile
Worst babysitter: Spider-Man
Panels from Marvel Team-Up #133 (September 1983), script by J. M. Dematteis, pencils by Sal Buscema, inks by Mike Esposito, colors by Bob Sharen, letters by Diana Albers
And, oddly enough...
Best babysitter: Doctor Doom
Panels from Fantastic Four #258 (September 1983), script, pencils, and inks by John Byrne, colors by Glynis Wein, letters by Jim Novak
Then again, as soon as the parents are out of the house.,..
Ah well. No babysitter is perfect. At least he doesn't rummage through your dresser drawers.