Speaking with ET's Samantha Harris at the "Killers" promotional junket at the weekend, Katherine explained that although it had been a very difficult choice to leave "Grey's Anatomy", the opportunity to bond with her daughter Naleigh over the past few months was something that she is extremely grateful for.

"As much as I miss my friends [on the show] and wonder what Izzie's storyline would have been in the season finale, I am so, so grateful that I chose to give [Naleigh] this time. She and I needed it."

"She's just getting more and more fun every day, like the walking, the talking and mimicking," added the proud mom. "She's super-goofy and has a great sense of humor which is just awesome for us, because we love to laugh."

"It's been really amazing to have that time with her, for sure, and to be just Mom, and be involved and be in charge," Katherine said. "And so now it's hard to go back to work, but there is a big part of me that's anxious to go back to work."