The stars showed up to speak at the Live Earth press conference in New York on Tuesday (13Oct09), where they both addressed the need for clean drinking water in third world countries.

The actress, who is preparing to scale Mount Kilimanjaro to raise money for the cause, admitted she hadn't realised that millions of people around the globe have no access to drinkable water.

She told reporters, "For most of my life, water has been an ordinary part of an ordinary day. Turn on the faucet, get in the shower, wash your clothes. It is always there; it is always accessible. I've never been forced to think about where it comes from.

"I won't stand up and tell you that learning more has made me the brilliant creator of solutions; I am not. But I am listening. And I am changing the way that I live. This isn't a problem for them or for those - this is a problem for us and for we."

The Fall Out Boy bassist added that he has become increasingly concerned for children's health since becoming a father.

He added, "It's mind-blowing to me that every day 5,000 kids die because they're drinking water that's unsafe. These are regular kids, just like my son, who have to walk miles each day to get water and the water you get may not be safe or clean. If I had to give my little guy a glass of water - well, he doesn't drink a lot of water - but if I had to give my little guy a glass of water knowing that it would make him sick, it would totally freak me out."

Wentz welcomed his first child, son Bronx Mowgli, with wife Ashlee Simpson in November (08).