The Eucharist they don't need, as they are not capable of sinning. As a Catholic I take the Holy Scripture literally, and literally it teaches that baptism is necessary for salvation. There is an extrascriptural speculation that the innocent babies slaughtered in the Holocaust of abortion are saved by the extraordinary mercy of Christ, together with the Holy Innocents. There is another that they receive baptism of blood similar to the Good Thief. At any rate, they do not experience any pain of Hell due tot their innocence. St, Augistine taught that they are in a region of hell where they have all possible natural happiness, but deprived of the supernatural happiness of heaven. This is, best that I know, the range of Catholic thought on the subject. Also see Limbo.
But Jesus said, Suffer little children, and forbid them not, to come unto me: for of such is the kingdom of heaven. - Matt 19:14
The LORD [is] gracious, and full of compassion; slow to anger, and of great mercy. - Psalms 145:8
For he saith to Moses, I will have mercy on whom I will have mercy, and I will have compassion on whom I will have compassion. - Romans 9:15
We are ALL born with a sinful nature. Babies are innocent but they ARE sinful because of the nature with which they are born into this sinful world. I doubt very much that there are ANY babies or children in hell, not even in limbo.