Can kids have meat or grape juice during the Nine Days?

During the Dine Days, Ashkanazim do not eat  meat or drink wine or grape juice. However,   for children that are 5 and below, you  are allowed to feed them meat and give   them grape juice. Between the ages of 5 and 8  or 9, they should not have meat or grape juice.   When it comes to those children who  can't stay up for the late meal on   Friday night and you generally feed them their  Shabbat meal an hour or two before Shabbat,   you're allowed to give them meat and grape juice  during that meal because in their mind it is the   Shabbat meal. Once they are at the age of 8 or 9,  where they understand the concept of mourning for   Yerushalyim, then they should not have any  meat or grape juice during the Nine Days.