You might think that at age 63, Kelsey Grammer would be exhausted from having three children under the age of six at home. But the opposite is true. "It's fantastic — the energy is magnificent," he exclusively gushed to Closer Weekly at the Israeli Consulate's recent 70th Anniversary of Israel celebration in LA. "I'm as young as they are." Given the difficult times he's been through in his life, it's no surprise the Frasier star is reveling in his current bliss.

"[My wife, Kayte Walsh], has a pristine and extraordinary ability to love," he raved of his fourth wife, whom he wed in 2011 (they've renewed their vows since). "She loves being pregnant and being a mom." Kelsey's equally psyched about being a father, especially now that he's older.

kelsey grammer kids

Kelsey with daughter Mason and son Jude.

"When you reach a certain age, you don't worry about your career the same way," the star, who had two kids with his third wife, Camille Grammer, said. Earlier in life, "your kids get a little lost in the shuffle, and you end up regretting it." Still, Kelsey has learned from his mistakes. "He becomes a better dad after every child," daughter Mason, 16, told Closer at the recent Race to Erase MS Gala in LA. "When I grew up, he was very strict. Now he's more relaxed with my younger siblings. It's a blast!"

Family life has often been a source of heartbreak for Kelsey in the past. His father was murdered by intruders when Kelsey was a teenager, and two of his brothers died in a scuba-diving accident.

In 1975, his younger sister Karen, 18, was killed by thieves who thought she'd witnessed their unsuccessful attempt at robbing a restaurant. "I was her big brother — I was supposed to protect her, and I could not," Kelsey previously told Vanity Fair. "I have never gotten over it. It very nearly destroyed me." Over time, "I have learned to forgive," he's said, but he has testified at parole hearings to keep her killers behind bars. "I accept that you live with remorse," he said to one of them at a parole hearing. "But I live with tragedy every day."

kelsey grammer and his wife

Kelsey and his wife, Kayte.

Playing Dr. Frasier Crane on Cheers and its spin-off, Frasier, proved therapeutic for Kelsey. "We really were like a family," he said of his co-stars. "For 20 years, I was going to the same studio, so it was like going to graduate school at a favorite college."

These days, he finds his greatest happiness at home. "My youngest son, James, is walking, and talking, and eating all the time," he beamed of his one-year-old to Closer. "And my four-year-old, Gabriel, is starting to figure out stuff. They discover things every day. It's wonderful."

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