THE 4-year-old boy who drowned in Tommy Lee’s pool during a birthday party died because his au pair left the party early without asking another adult to supervise him.

That’s the shocking claim of Judy Ziehm, who told The ENQUIRER in an exclusive interview that young Daniel Veres’ male au pair asked her ONLY to drive the little boy home after the party — not to watch him.

But the dead boy’s parents are blaming the June 16 tragedy on Ziehm — a 52-year-old former actress who’s appeared in the soft-core porn films “Flesh Gordon” and “Star Virgin.”

“If Judy Ziehm is claiming that she had no responsibility to look after the boy and only offered to take him home, then she’s mistaken,” said a friend of the child’s parents. “She volunteered to look after Daniel.”

An in-depth ENQUIRER investigation reveals the tragic chain of events and conflicting claims that resulted in the child’s death after he was left unsupervised.

Even though the pool was surrounded by adults, Daniel was unseen after he slipped under the water because the pool has a black bottom and it was filled with toys, The ENQUIRER has learned.

Ziehm described the key events from the fifth birthday party of Tommy Lee and Pam Anderson’s son Brandon to The ENQUIRER.

“Daniel’s au pair, Christian Weiss, approached me at about 2 p.m. and asked me if I’d give Daniel a ride home,” said Ziehm, a professional babysitter who was watching three other children at the party.

“I agreed. But I told him to make sure that either he or Daniel’s mom, Ursula, call me and verify that it was O.K.

“I gave Christian my cell phone number and waited for him or Ursula to call me.

“I got several cell phone calls during the party.

“But I never heard from Christian or Ursula. So I figured other arrangements had been made for Daniel.

“Meanwhile, Daniel was fully dressed and watching a magic show with the other children.

“At some point during or after the magic show, Christian left to go to a concert. He never even notified me he was leaving.

“After the magic show, Daniel said he wanted to jump back in the pool.

“But he was too shy to change into his suit at the pool, so I took him to the house to change.

“After he changed, I took him back to the pool and put him in the very shallow end, where Tommy Lee and the other parents were lounging.

“The water was shallow enough for Daniel to sit down in and play with a squirt gun.

“Then it was time for Brandon to cut his chocolate-and-strawberry birthday cake.

“Daniel got out of the water and had some cake. But he quickly headed back to the pool with the other children.

“I left the pool to take two of the children I was caring for to the bathroom.

“The last time I saw Daniel, there were plenty of adults in and around the pool. Some were merely arm’s length from him.

“When I returned, Daniel was being fished out of the water.

“I rushed to him and felt his leg. He seemed alive. His skin was warm and rosy.

“And he was throwing up, so I thought he’d be O.K.

“But everyone was frantic, trying to save Daniel at once. Parents were all over him, pulling and tugging at him.

“Someone shouted, ‘Everyone, settle down!’ But the confusion continued.

“At one point a fight broke out among the parents and Tommy’s assistants, with people shouting, ‘We’re doing the best we can!’

“There was a lot of complaining that CPR was not being administered correctly.

“It was pure chaos.

“No one has said publicly that there was booze at the party but coolers filled with beer appeared at about 2 p.m.

“And that may have contributed to the panic that ensued when Daniel was found in the water.”

But Daniel’s parents have a different version of events, says the family friend.

“The parents believe the story of their au pair — who’d lived in their home and proven himself entirely honest and trustworthy. He is now back in Germany.

“Daniel’s parents, James and Ursula Veres, had agreed that Christian could bring Daniel home at 2:30 so he could go see a Wango Tango concert.

“But Daniel was having such a great time at the party that he pleaded with Christian to let him stay.

“Judy Ziehm — who was a nanny to one of Daniel’s friends and was known to the boy — offered to look after him and take him home later.

“Christian knew the Veres family knew Judy, so he felt comfortable handing the boy over to her.”

The ENQUIRER has also discovered that Christian’s English was less than perfect, possibly contributing to a communication gap between he and Ziehm.

The Veres’ family friend continued: “Mrs. Ziehm offered a piece of paper with her cell phone number on it and told Christian that the parents could call her.

“Christian left for the boy’s home and told the parents what had happened.

“He gave them the woman’s name and cell phone number, then left for the concert with their blessing.

“The parents tried to call Judith Ziehm’s number, but could never get through.

“Now they’re sickened and angry.

“They’ve been told by other witnesses that the woman was not looking after their son.

“They’ve left messages for Judith Ziehm on her cell phone and home phone. But they haven’t heard from her.”

The parents, who have consulted a top litigation attorney, may file suit against Tommy Lee.

“He had a pool party — without adequate security and negligent conditions in the pool,” said the family friend. “It’s a black-bottom pool and so many pool toys were on the surface that you couldn’t even see in the water.

“And with so many kids, the party clearly needed a lifeguard.”

Ziehm insists she’s not to blame for the tragic accident — and says she hasn’t gotten any messages from the Veres family or their attorney.

“Daniel’s au pair wanted to leave the party early to go to a concert,” she said.

“At the last second, he asked me to give Daniel a ride home with the other kids I was chauffeuring.

“My guess is that he didn’t ask anyone to care for Daniel.

“He simply assumed that since all the parents knew the boy, we’d keep an eye on him.

“That was his big mistake. He left Daniel alone.

“My conscience is clear. I’m not happy about what happened, but I know I’m not to blame.”