The U.S. Coast Guard suspended the search Thursday for a Port St. Lucie man who went missing while on a Carnival cruise earlier this week. Danielle McGrath says it is very out of character for her brother Kevin to take off or cut off communication, but on a family trip, he disappeared without a trace.Cellphone video captured Kevin McGrath dancing to the music on a Carnival cruise Sunday evening, and then..."We know that at 3:30 in the morning, he used the key card to get back in the room, and anytime between then and 7:30 in the morning when he was supposed to meet my family for breakfast is when he went missing," his sister said. 'Not like my brother': Sister of man missing from Carnival cruise ship speaks out Danielle McGrath said when her brother didn't show up to disembark later either, they demanded Carnival Cruises check surveillance, but still no answers. "I guess they have some type of sensors where it triggers if someone falls overboard, and they said nothing went off," she said. So, they contacted Miami PD and federal authorities. "The U.S. Coast Guard, they have been amazing; they searched the water top to bottom, left to right, everything you can think of, and they even came out to Port St. Lucie," Danielle said.It was to tell them they haven't found any trace of the young father of two. An Army veteran who served overseas, McGrath had just moved his family back to the Treasure Coast."It is definitely not like my brother to just up and go missing," Danielle said. Kevin was out the morning he went missing with his twin brother Andre. The whole family had boarded the ship to celebrate their dad's 60th birthday."Kevin, please, wherever you are, I need you home safely. We love you, we miss you, and we cannot take this," Danielle said.Along with her family, she's asking anyone on that cruise ship who may have seen or heard something to call Miami police.