Should the sneezing child who has not yet spoken be told, "Yarhamuk Allah," or should "Alhamdulillah" be said on their behalf?

A young child, upon sneezing, should be supplicated for with blessings and righteousness, and similar phrases, even if they do not say "Alhamdulillah" (Praise be to Allah). Examples include: "May Allah bless you," and one might add: "May Allah mend your affairs" or "May Allah make you righteous." It is also said that their guardian or anyone present should say "Alhamdulillah" on their behalf, and then the aforementioned supplication should be made for the child.