When an older sibling has figured out the Santa story
Let your older child choose whether to help. Adults can handle the younger children’s questions.
An older child may know the answer and still love a stocking. Ask privately whether they want to help prepare anything. Some enjoy choosing a book for a younger sibling; others are tired of being asked to act excited on cue.
Give the older child a simple way to respond
You can say: “Your brother enjoys the Santa story. If he asks about it, let us answer.” That is more manageable than a demand to keep a secret forever. If relatives celebrate in both English and French, ask them to use the same gentle approach rather than putting either child through a performance.
Keep the older child’s own Christmas visible. They can choose the board game after supper or help with baking without having to become an assistant to Santa. If a younger child finds out, listen and respond; do not blame the sibling who spoke.