the children

Ezra 6:16
Then the people of Israel--the priests, the Levites, and the rest of the exiles--celebrated the dedication of the house of God with joy.

kept

Exodus 12:6
You must care for it until the fourteenth day of the month, when the whole assembly of the congregation of Israel will slaughter the animals at twilight.

Joshua 5:10
On the evening of the fourteenth day of the month, while the Israelites were camped at Gilgal on the plains of Jericho, they kept the Passover.

2 Chronicles 30:1-35:27
Then Hezekiah sent word throughout all Israel and Judah, and he also wrote letters to Ephraim and Manasseh inviting them to come to the house of the LORD in Jerusalem to keep the Passover of the LORD, the God of Israel. . . .