When God wants to bless someone but realizes that the person's tongue could make them lose the blessings; if they don't have the needed discipline to control their tongue, God could choose to make them temporarily dumb till the blessings manifest. You can ask Zecharias, the father of John the Baptist.

Should I pray this prayer for someone?

"May God make you temporarily dumb till your blessings manifest, if that is the only way He can help you, in Jesus' Name. Amen"

Any "Amen"?