O'Neal rose to fame much the same way Spears did and says she can empathize with Spears because she was once labelled an "unfit mother" herself, imdb.com reports.
O'Neal said: "I relate to her and feel really sad for her. I did everything that she doesn't want to do. I did the drug testing. It was very humbling but I wanted those kids back. Hopefully she will figure (it) out. But it's going to be hard and she will do it publicly and that sucks."
O'Neal was the youngest person to ever win an Academy Award in "Paper Moon" (1973). She lost her children to her ex-husband John McEnroe after their eight-year marriage ended in 1992. She has since undergone long-term treatment for substance abuse.