Austin Stephanos, left, and Perry Cohen, both 14 years old, are shown in this photo provided by the U.S. Coast Guard in Miami. (U.S. Coast Guard via Reuters)

At first there was optimism. Then there was hope.

Now there is nothing but prayers left in the search for two Florida teens lost at sea.

The families of Perry Cohen and Austin Stephanos have called off their private search for the 14-year-olds, who went missing on a fishing trip July 24.

The Coast Guard suspended its own search more than a week ago, but the families held out hope that their sons would be found.

On Sunday, that hope gave way to a grim reality.

“Absent new information, continuing the search is not practical,” the families said in a joint statement announcing the end of a large-scale, contractor-led search for the teens.

The families said they will continue smaller expeditions — led by family, friends and volunteers rather than paid professionals — for their sons, who were last seen fueling up their 19-foot boat near Jupiter, Fla.

“We love our boys and want them home. Today, our hope becomes our prayer — that one day Perry and Austin will be returned to us. We thank everyone for their dedicated efforts and support,” the statement also said.

“We will never stop looking for our boys, Austin and Perry,” the statement continued. “We ask that you join us in our prayer that one day Perry and Austin will be reunited with their families.”

The 16-day search for the missing teenagers gripped the nation, as did the debate over whether two kids not old enough to drive should have been allowed such freedom.

Many people took to the Internet to accuse Austin and Perry’s parents of poor parenting.

[Marine experts say missing Fla. teenagers should not have been alone offshore]

Perry’s stepfather, Nick Korniloff, acknowledged that criticism in an interview with CNN three days after the boys’ disappearance but said the boys weren’t supposed to take the boat offshore, let alone towards the Bahamas, as speculated.

“Anybody who wants to judge and look back and ask why these boys went out there, they can do that,” Korniloff said. “We know who our children are, and people who live on the water know what the water is all about and how we raise our kids.”

Perry’s mother, Pamela Cohen, added that there was little they could do to stop the intrepid teens from taking the boat out when nobody else was home.

“We can’t keep them under our eye every moment of every day,” she told CNN. “We raised them right and hopefully they will make the right decisions, and I do believe that they have the knowledge and the strength to get them through this.”

Austin’s mother echoed the same faith in her own fearless son.

“Austin has been on the water since before he could walk, ” Carly Black told NBC’s “Today” show. “This is his fourth boat. This isn’t new to them. These boys have been doing this … it’s not even second nature at this point. It’s in their blood.”

But a massive combined Navy and Coast Guard search turned up nothing but an empty boat.

The Coast Guard ended its search for Austin and Perry a week after their disappearance.

“I hope that at some point in the future, they can take solace from the fact that hundreds of people searched thousands of miles because we were desperately committed to try to find Austin and Perry,” Mark Fedor, chief of response for the Coast Guard 7th District in Miami, ominously said at a July 31 news conference. “That is my hope.”

But the families held out their own hope.

“We are continuing the search for Perry and Austin and not giving up until they are rescued,” they said in a statement that same day. “The next 48 hours are critical, and the family and friends are offering $100,000 for the safe return of the boys.”

“As the sun rises another day, it is a mothers prayer that you will be safe and sound in our arms today,” Cohen wrote on Instagram. “This evening sky will be illuminated by a Blue moon. It seems to be too special of a day.”

But as the search entered its second week, hopes of a dramatic ocean rescue began to fade with each passing day. (A week is about as long as someone can survive without fresh water, experts say.)

And although the families have vowed to keep searching for the lost teens, their disappearance has shifted from a debate over parenting to a warning over the power of the open sea.

“It’s a warning call for everyone else unfortunately for what could happen to you,” Coast Guard Petty Officer Mark Barney told The Washington Post.

“The water is a very dangerous place that can seem very safe,” marine expert Rick Spilman added. “You can see the shore, it’s beautiful, you can get caught up in the color of the water and the dolphins and the birds, and you feel so much a part of all of it. If you get caught up in the wonder, you forget this place can also kill you.”

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