Israeli police said the two boys appear to have been stoned to death after going on a walk Tuesday. Israeli troops detained 15 Palestinians for questioning.
Doctors say the baby is in fair condition but the mother's wounds are serious.
In other incidents, Palestinian police say Israeli forces entered a Palestinian-ruled area near the town of Beit Hanoun in northern Gaza, demolishing a police post. Palestinians fired mortar shells at Nissanit, a Jewish settlement in northern Gaza, and at the Kfar Aza kibbutz across the border inside Israel. Palestinian peace negotiator Saeb Erekat denounced the killings, saying the Palestinian Authority considers killing children and civilians, either Palestinian or Israeli, unacceptable.