Check out Jennifer Garner's look-alike nanny! The mother-of-three was SERIOUSLY twinning with her kids' babysitter on Tuesday, as the two wore grey tops, matching jeans, the same white sneakers, dark sunnies and even the same length brunette hair, parted down the middle! They were even both drinking LaCroix sparkling water, her goodness' sake!

We spotted the pair walking to the car after pick-up at daughter Seraphina and son Samuel's school -- immediately after, Jen took Sera for a quick snack at the Brentwood Country Mart before the 9-year-old's karate class.

And as Jen keeps the family running smoothly while the kids' dad Ben is in rehab, the actor himself is trying to clean up in more ways than one!

We spotted Ben taking leave of The Canyon treatment facility in Malibu to visit his Beverly Hills dentist yesterday and it didn't look fun! In fact, isn't nitrous oxide (laughing gas) off-limits for addicts? Ben looks like he had a serious does as he rode back to Malibu in the car, chauffeured by a sober coach from the facility. Hey, whatever it takes!