Question: Am I allowed to feed meat to young children during the nine days?
Discussion: The Remo (Orach Chayim Siman 551 se’if 10) writes that the minhag is not to drink havdolo wine during the nine days [i.e. on motzo’ei Shabbos Chazon]; instead the wine is given to a child to drink (and if there is no minor then the person making havdolo can drink the wine himself).
The Mishna Berura (ibid s.k. 70) defines the age of the child mentioned by the Remo as a child who has reached the age of chinuch [for brochos], but has not yet reached the age of [understanding] aveilus hachurban.
The Magen Avraham (ibid s.k. 31) infers from this Remo that one is allowed to feed young children meat and wine during the nine days and explains that originally the prohibition of meat and wine was never decreed on young children (i.e. children who are not old enough to understand aveilus hachurban). [The Pri Megadim (ibid) explains that since the original gezeiroh of meat and wine only pertained to se’udah hamafsekes and not to the nine days, when the chumrah developed to refrain from meat and wine during the entire nine days it was not accepted to include young children.] The Chaye Odom (Klal 133) similarly rules that it is permitted to feed meat and wine to young children during the nine days.
However, both the Dogul Mervovo and Levushei S’rod learn that one may not feed meat and wine to children [even under the age of chinuch] during the nine days. The only dispensation is l’tzorech mitzvoh (and that is why havdolo wine may be given to a child to drink).
Therefore, there is a fundamental macklokes regarding the reason that the Remo allows giving havdolo wine to a child to drink: According to the Magen Avraham and Chaye Odom there is no restriction at all to feed young children meat and wine, and it is even permitted when there is no tzorech mitzvoh; however, according to the Dogul Mervovo and Levushei S’rod there is technically an issur, but the issur is waived l’tzorech mitzvoh.
The Mishna Berura (s.k. 70) writes that this dispensation of giving the havdolo wine to a child to drink is specifically in a situation of a mitzvo; otherwise one may not feed meat and wine to healthy children – even if the children have not reached the age of [understanding] aveilus hachurban.
The p’sak of the Mishna Berura (that one may not feed meat and wine to children even under the age of chinuch except for tzorech mitzvo) is clearly in line with the Dogul Mervovo and Levushei S’rod and (uncharacteristically) unlike the Magen Avraham and Chaye Odom (c.f. Sha’ar Hatziyun s.k. 76 where the Mishna Berura asks on the Chaye Odom why he sides with the Magen Avraham who is a lone opinion amongst the other Poskim).
Conclusion: The clear ruling of the Mishna Berura is that one should not feed meat and wine even to children under the age of chinuch during the nine days.
However, several important exceptions to this should be noted:
• Regarding very young children (2 or 3 years old) Rav Wosner is quoted as saying that there is no restriction at all to feed them meat during the nine days.
• It would appear that if there is a nutritional benefit for the child (e.g. the child will not eat other proteins besides meat or chicken) and it is not just a convenience for the parent, then one can certainly rely on the lenient opinions (i.e. the Magen Avraham and Chaye Odom) and feed the child meat during the nine days.