Five-year-old Ahmed Dawabsha, his uncle and his grandparents were to fly from the Jordanian capital Amman to Spain, his grandfather said.
"We have been invited by Real Madrid, but we don't know yet which day we will be able to meet the players," Hussein Dawabsha told AFP.
Palestinian Football Association head Jibril Rajoub welcomed the "superb humanitarian gesture by Real Madrid, its administration and Cristiano Ronaldo, who are restoring hope for a child who lost his entire family."
"There is an unknown soldier in this initiative and that is Zinedine Zidane, who we warmly thank," he said of the Real Madrid coach.
The July 31st attack on the Dawabsha family home in the village of Duma in the occupied West Bank killed 18-month-old Ali Saad Dawabsha and fatally wounded his parents.
Ahmed, who was hospitalised after the attack with severe burns, was the sole survivor from the immediate family.
The attack drew renewed attention to Jewish extremism and accusations Israel had not done enough to prevent such violence.
It also drew international condemnation and worsened tensions between Israelis and Palestinians.