There is some precedent for use of the term p(a)edicide or p(a)edocide, combining p(a)edo- from ancient Greek "boy, child" (see Etymonline; compare pediatrics, pedophile) and the common murder suffix -cide1.
Some examples from the literature (all bolding added):
[N]o distinction between infanticide or pedicide (killing of children) is implied unless specified.
—Sarah Blaffer Hrdy & Glenn Hausfater, Infanticide: Comparative and evolutionary perspectives, 1984
"Pedocide" has been used at times to denote the killing of any child, or the killing of a child between the age of one and sixteen years. Adelson defined post-infancy "pedicide" as the killing of a child who has emerged from infancy but not yet attained the age of fifteen years.
— Larry Milner, Hardness of heart/hardness of life: The stain of human infanticide, 2000 (footnotes omitted)
Three types of filicide include (1) neonaticide, the murder of a child less than one day old; (2) infanticide, the murder of a child older than one day and less than one year old; (3) pedicide, murder of a child older than one year and less than age sixteen.
–Applied criminal psychology: A guide to forensic behavioral sciences, Richard Koosis, ed., 2009
As you can tell, the definition of the term is not strictly defined in terms of age, but since this is also true for childhood I think you could shape it to suit your needs.
Although it is a rare word, it appears to be at least somewhat familiar within the scholarly fields that regularly discuss this crime, and is probably transparent enough etymologically to be understandable by most readers.
On the spelling issue: Etymonline suggests that the British spelling with A is preferable, to avoid confusion with the Latin prefix meaning "foot"; I think in context it would probably be clear enough without, if you are writing for a North American audience (of course, use paed if writing for an audience that uses British spelling). The choice of -o- or -i- is a little less clear-cut, but the spelling with -i- seems to be more common, per Google Ngram (though both are so rare that if you have a good reason to prefer the other spelling I think it would be fine).
So ultimately, your sentence could read something like:
You have been charged with multiple counts of paedicide.
1 Purists will note that -cide is ultimately from Latin, not Greek; however, this kind of mixing of source-languages in words coined by English-speakers is not-uncommon, particularly when the two roots are most familiar in contrasting forms, as here. Wikipedia has a list of such hybrid words, including such familiar coinages as automobile and genocide.
For a purely Latin term, thanks to @Patrick M for puericide, which has been listed as a synonym of infanticide. Pueri- is from the Latin cognate of p(a)edo- (compare puerile). This term appears to be much less common than pedicide and company, with fewer than 30 results for puericide in Google Books versus about 200 for pedicide plus more for other spellings. I suspect this may be because the p(a)ed- prefix is more familiar to English-speakers than puer-, making the full term more immediately understandable.