LOS ANGELES (AP) — A grieving father who sang the Beatles' ballad "Blackbird" as his infant son clung to life told mourners that he was overwhelmed by the outpouring of prayers and support after a video of the tender moment gained widespread Internet attention.Chris Picco said Saturday at a memorial service for his wife, Ashley, and their son, Lennon, that he didn't have enough words to express his gratitude to those who reached out to him, including strangers apparently touched by his story.They died this past week after Ashley became ill while pregnant and Lennon was delivered prematurely."I could never articulate how much your support and your strength, and your prayers, and your emails and your Facebook messages and your text messages ...