United Kingdom, Sept. 22 -- Reese Witherspoon "grieved" her eldest children when they left home for college.

The 49-year-old actress was full of tears when her daughter Ava, 26, and her son Deacon, 21 - who she shares with her ex-husband Ryan Phillippe - went away to study.

Reese made the admission on the latest episode of the New York Times' The Interview podcast, and told host Lulu Garcia-Navarro: "I grieved their going to college, and I cried in their rooms.

"One year, one of them didn't come home for Christmas, and I sat in their bed and just cried."

The Morning Show star said she felt a "loss" because the kids were not around.

Reese - who is also mom to her 12-year-old son, Tennessee, whom she has with her 55-year-old ex-husband...