I am a star! Okay, not really, but recently I felt like one. I was in a play put on by some women in my community. Fortunately, I was cast as the grumpy, miserable old man who had all the best lines, and I even managed to squeeze in a few of my own adlibs that got roars of laughter from the audience.

For the next few weeks I couldn't walk down the street without women stopping me to tell me how much they enjoyed the play and how much they laughed. I was a real celebrity!

But with celebrity sometimes comes ego, as Marlon Brando once said, "An actor's a guy who, if you ain't talking about him, ain't listening." Lucky for me, there were some wise women in my neighborhood who pointed out that my part in the entertainment wasn't about me and my comedic talent. It had a Divine purpose. "Keren!" they said, "these ladies come to see the play with all their troubles and worries and you made them holler with laughter! What a mitzvah!"

I had never thought about it that way. Not only did I get to be up on stage doing something I really enjoyed, but I was actually doing something that had true worth?

There is a Talmudic story which substantiates this principle. Elijah the Prophet sees two people who have a secured their places in the World to Come. He asks them what they have done to merit this, and they answer that they made people who were depressed happy, and they helped people who were arguing to make peace. Of all the great deeds in the world, this Talmud specifies cheering people up and getting people to make peace as the two things that will get you into Heaven.

As I caught myself patting my own back, I was still slightly plagued by guilty feelings that this whole acting business was just one big ego-fest. Come on, was laughter really that important?

Around the time of the show, my three year old son Mordechai got sick. He was pale at first, then lethargic, until finally he couldn't even walk. For a few weeks the doctor tried to placate us with various unsatisfactory diagnoses, until we finally insisted on a blood test. And then we learnt the truth -- my little boy had Leukemia.

What a turn around. Now women were stopping me in the street for a different reason. Just a few weeks ago they were congratulating me, now they were commiserating with me, offering help, telling me that they were thinking of me.

It was in this very dark time that I realized just how important and valuable laughter can be.

It was in this very dark time that I realized just how important and valuable laughter can be.

My son stayed in hospital for the first week after his diagnosis, and he hardly had the energy to move from his bed. He had had an operation to insert a portacath -- a pediatric catheter used to administer chemotherapy - and was extremely sore. He wasn't interested in toys, books or music. To make matters worse, he was on medication that made him moody and grumpy. This was extremely difficult to watch because normally, he's a very happy child. Many parents will tell you that as long as child is happy, any hurdle can be overcome emotionally, but a miserable child is the most down-heartening thing on earth.

During that first week, we had a visit from the Clown Doctors. These are actors employed by the hospital to go around the pediatric units and entertain the children. At first, the particular Clown Doctor who came to visit Mordechai got a cold reception. I wasn't even sure the Clown Doctor's efforts were worth it -- Mordechai's frown seemed to be a permanent fixture. But then, suddenly, after several minutes of silly antics, Mordechai laughed!

What a blessing to hear that little giggle! What an incredible uplift to see a smile on his face! Everything had been so heavy, he had been so miserable, there had been so many tears, and now he was laughing! Suddenly I felt that it was possible, even in these circumstances, to have happiness and laughter. It made our situation bearable again.

After those first few weeks of treatment, Mordechai started to feel much better. He is still undergoing rigorous chemotherapy and has another two and a half years of treatment to go, but most of the time, he feels well and is happy.

And every time I hear him laugh, every time I see him enjoying himself, I still get that wonderful feeling of encouragement. For me, when the situation is challenging or I am feeling weighed down with stress, hearing a good joke, watching something funny -- just being able to laugh despite what's going on, is a tremendous release, and instantly helps to reduce the pressure.

People who have the ability to make people laugh have been given a great gift. The next time I'm in a performance, I'll have to remind myself of that.

Keren's son's full Hebrew name is Mordechai Yehuda ben Keren Gila should anyone wish to pray for him.