Question: May one answer Amen to a blessing recited by a young child?
Answer: The Baraita in Masechet Berachot (53b) states, “One answers Amen to a blessing recited by anyone except for young children. However, this only applies when they are learning how to recite the blessing with their rabbi, but if they are reciting the blessing in order to exempt themselves, Amen is answered to their blessings.”
Maran Ha’Shulchan Aruch (Chapter 215) explains this to mean that it is permissible to teach children the proper way to recite a blessing even though one is reciting a blessing in vain, for when one teaches a young child to bless, this is done even when the child has not done anything (or eaten anything) to require a blessing. For instance, if one wishes to educate one’s child to recite the “Boreh Peri Ha’etz” blessing, one may ask him to recite the blessing several times on the same fruit although halachically, he should only be reciting the blessing once. One should therefore not answer Amen after such blessings, for one cannot say Amen, which is in essence verifying and affirming the words of the blessing, when the blessing is not a blessing at all.
However, if they are reciting a blessing to exempt themselves (i.e. they are actually performing an action which requires the recitation of a blessing), since they are obligated to recite blessings before the age of Bar/Bat Mitzvah based on the Mitzvah of educating them, one should indeed answer Amen to their blessing.
Nevertheless, the Acharonim point out that this applies only to children who have reached the age of education, which is when they understand the idea of blessings and know to Whom they are blessing; however, one should not answer Amen to the blessings of toddlers and very young children, for we must be concerned that their body is not properly clean. Thus, when the Tur and Maran Ha’Shulchan Aruch write that one should answer Amen to the blessings of children when they are reciting the blessing in order to exempt themselves, this refers only to children who have reached the age of education. Maran Rabbeinu Ovadia Yosef zt”l writes that because this age is doubtful, one should answer Amen only when the child is nine years of age and above.
Based on this, one should educate one’s children to clean their body very well, for if they do not clean themselves well after using the facilities, all of their blessings and prayers will have been in vain.
Similarly, just as it is necessary to educate children to recite blessings, it is likewise necessary to educate children to answer Amen to blessings. When the child sees adults not answering Amen to his blessings, he may treat answering Amen lightly since he does not understand why no one is answering Amen to his blessings. For this reason, when a young child would recite a blessing next to Hagaon Harav Shlomo Zalman Auerbach zt”l, he would subtly answer “Ameh” (without the final “n”) so as not to complete the word. The child would therefore not realize that a proper Amen was not being answered to his blessings and in this way, he would nonetheless be educated with regards to answering Amen.