A survivor of the deadly boat capsize in New York Harbor has described how she held the baby killed alongside her mom just moments before tragedy struck. Elizabeth Velez was handed Antonella Garcia to help the five-month-old girl’s mom Sara Sanchez, 27, try to fit her with a life jacket — even though prosecutors say there were no child-sized ones available, and the 14 friends on board were not made to wear them. “She was a very happy girl. She didn’t cry the whole way,” Elizabeth Velez told NBC New York of the tot killed with her mom moments later…