The first funerals are to be held for victims of Friday's shootings at a school in the US state of Connecticut.
Noah Pozner and Jack Pinto, both aged six, will be buried after ceremonies at 13:00 local time (18:00 GMT).
Twenty children and six women died in the assault on Sandy Hook school by a lone gunman who then took his own life. He had earlier killed his mother, reports the BBC.
On Sunday President Barack Obama told residents at a vigil in Newtown the US must do more to protect its children.
He said he would use the powers of his office to prevent a repeat of the tragedy, adding that the nation shared the townspeople's grief.
"We can't tolerate this any more," Obama said. "These tragedies must end and to end them we must change."
He made no specific mention of new gun control measures, but BBC North America editor Mark Mardell says this is the strongest pledge a president has ever made to wrestle with the powerful gun lobby.
Meanwhile, West Virginia Senator Joe Manchin, who supports gun ownership and has been given an "A" rating by the National Rifle Association, told US network MSNBC that it was time to "move beyond rhetoric" on gun control.
Manchin, a gun owner and frequent hunter, said: "I've never had more than three shells in a clip. Sometimes you don't get more than one shot anyway.
Manchin is the first NRA-backed US senator to speak out since Friday's killings.
In Connecticut, Jack Pinto will be buried in the Newtown Village Cemetery, and Noah Pozner will be buried at the B'Nai Israel Cemetery in the nearby town of Monroe, according to local media reports.
The family of James Mattioli, six, is also holding a wake on Monday.
Other victims' funerals will be held throughout the week.
Jack Pinto was described as a sports lover, and reports say he may be buried in the No 80 jersey of his idol, New York Giants football player Victor Cruz.
Cruz played in a game on Sunday with the boy's name written on his shoes and gloves.
Noah Pozner was the youngest victim of the shooting, described by his family as inquisitive and mature for his age.