The girl found the empty McDonald’s cup outside.

On another occasion, to her excitement, Kevin planned to take the girl to a family birthday dinner. But he never showed. Kevin called later, hysterical and suicidal, saying he never showed because his grandmother had fallen down the stairs.

“This person is schizo with multiple personalities,” said the girl, who asked not to be identified because of several stalking episodes.

By mid-2011, Kevin continued his romances, but from Spain, where he wrote that he had been forced to return because of a visa mix-up. But in June 2011, two days before he was to return to Miami to start medical school, the blog broadcast shocking news: Kevin died unexpectedly of cancer complications — he choked on his own blood.

The news stunned students, parents and teachers.

The San Roman family continued the blog, asking for photos of Kevin for a slideshow to be played at a funeral in Ibiza.

With her mother’s permission, Kaitlin sent Lucas a message of condolence through Facebook. She was also put at ease when a classmate claimed she had met the San Roman brothers at Dadeland Mall.

They struck up a friendship. Lucas claimed he was temporarily living in Tennessee, where little Katy was receiving treatment for her tumor.

Phone calls

Flirty text messages turned to phone calls. Kaitlin listened to Lucas as he cried over his brother’s death. Together, they watched movies and shopped at an online clothing store together.

Lucas promised to visit Miami soon. He even sent Masters a Facebook message asking for permission to one day take out her daughter. Lucas often charmed the family while on speaker phone.

At one point, Lucas even directed the family to a Chinese restaurant in Coconut Grove, where Kevin’s best friend treated them to a meal to go.

Lucas rarely spoke of Spain but gushed about his family.

Certainly, he had his quirks. His voice sounded child-like, and he displayed a juvenile streak much different from his brother’s personality.

Lucas, like his dead brother, was fiercely devoted to cancer causes. Kevin had promoted a fundraiser for a cancer-stricken St. Brendan’s girl, even buying T-shirts for sale at the April 2011 event.

In January, Lucas organized an Internet “prayer chain,” drawing hundreds of online supporters for a Belen Jesuit teen who was battling cancer.

Lucas wrote: “I lost my brother and best friend last year to leukemia. I don’t think anyone should go through the pain he went throughout his journey.”

One year after Kevin’s death, Lucas urged supporters to release balloons in his honor. Many did.

But time and again, something tragic happened every time Lucas was to visit Miami. Suspicions grew. The final episode: Katy, his little cousin, died days before the family was to throw her a birthday party here.

“He was bawling, crying hysterically,” Masters recalled of the late-night phone call Lucas made to break the news. “We didn’t sleep the whole night trying to comfort him. Looking back, how can someone be so cruel to use the illness of a child as part of their sick obsession of luring young girls into relationships?”

Then, Lucas claimed immigration forced his family to return to Spain. They continued talking via video chat, but the images went only one way — Lucas’ webcam was broken.