Jennifer Garner romper race seraphina stroller

Jennifer Garner and Ben Affleck's son Samuel can barely talk yet, but he's already participated in his first charity run!

The 2 year-old walked, jogged and strolled through the Kiddie K at this year's Home Run for Kids in Brentwood, to support the Upward Bound House. Sisters Violet and Seraphina were also in on the good cause.

Good job, kids! Next year ... the 5K!