отрок/отрочества

16:38 Dec 8, 2020 

Thank you, everyone, for this very interesting discussion and your suggestions!

16:31 Dec 8, 2020 

Yes, this is exactly what I wound up doing! I felt obligated to keep "boyhood" because of the Tolstoy reference, and continued using it in the following sentence. To my ear, "boyhood" does sound a bit old-fashioned. We do seem to like gender neutral words these days.

22:48 Dec 7, 2020 

3. A child, esp. a boy. Also figurative.

1788 W. Cowper Pity Poor Afr. A youngster at school, more sedate than the rest.
1852 H. B. Stowe Uncle Tom's Cabin ‘Now for the cake,’ said Mas'r George..; and, with that, the youngster flourished a large knife over the article in question.
1886 C. H. Spurgeon Treasury of David The wife is busy all over the house, but the youngsters are busiest at meal-times.
1916 C. A. Stickney Creevey Daughter of Puritans A substitute teacher has no real authority, and youngsters understand that perfectly.
1942 Short Guide Great Brit. There are..youngsters in knee pants..who have lived through more high explosives..than many soldiers saw..in the last war.
2009 N.Y. Times (National ed.) The small patch of concrete in the South Bronx features sliding boards and swing sets, along with a large fountain where neighborhood youngsters frolic happily through the spray.

22:47 Dec 7, 2020 

2.
a. A boy, youth; a young man, young fellow. Also, in the diction of pastoral poetry, used to denote ‘a young shepherd’. In wider sense applied familiarly or endearingly (sometimes ironically) to a male person of any age, esp. in the form of

1709 J. Byrom Let. 14 May in Private Jrnl. & Lit. Remains The other two sizers, one sophister, the other a Lancashire lad of our year.
1717 Lady M. W. Montagu Let. The young Lads..divert themselves with makeing Girlands for their favourite Lambs.
1720 D. Defoe Mem. Cavalier The old Lad was not to be caught.
1794 Sporting Mag. Requesting you as a brother lad of wax to make me some of your tight shoes.
1829 T. Hood Dream Eugene Aram in Gem My gentle lad, what is't you read?
1856 R. M. Ballantyne Snowflakes & Sunbeams What did you say struck you, Harry, my lad?
1871 R. Ellis tr. Catullus Poems Lovely the lady, the lad lovely, a company sweet.
1885 J. Ruskin Præterita All handsome lads and pretty lasses.

22:45 Dec 7, 2020 

6.
a. A young person; esp. a young man between boyhood and mature age; sometimes, esp. in earlier use, more widely (see quots.). Formerly sometimes (and still in dialect or vulgar speech) pleonastically qualified by young.

1711 T. Hearne Remarks & Coll. Wch was in the eleventh Year of his Age, and yt he was then a very hopefull Youth.
1774 tr. Chesterfield's Lett. Kal. To-morrow..you will attain your ninth year; so that, for the future, I shall treat you as a youth.
1805 Ann. Reg., Chron. Two youths, one 14 and the other 8 years of age, sons of a poor man.
1837 Dickens Pickwick Papers The pot-boy, the muffin youth, and the baked-potato man.
1881 19th Cent. Before she was twenty she wrote verses like other youths.

22:42 Dec 7, 2020 

3.
a. A male child or youth. Also: a son, irrespective of age (chiefly as referred to by members of the immediate family).Sometimes restricted to male children below the age of puberty, or below the school-leaving age.

1711 J. Swift Jrnl. to Stella I find I was mistaken in the sex, 'tis a boy.
1752 S. Johnson Rambler The sailor hated to see tall boys shut up in a school.
1812 Ld. Byron Childe Harold: Ah! happy years! once more who would not be a boy?
1844 A. B. Welby Poems A noble sturdy boy is he, and yet he's only five.
1866 S. B. Warner Word Driven from home, her boy put out of his birthright...
1908 R. Brooke Poet. Wks. The thing must End. I am no boy! I am No boy!! being twenty-one.
1945 E. Waugh Brideshead Revisited That..was Lord Sebastian Flyte. A most amusing young gentleman... The Marquis of Marchmain's second boy.
1989 M. Dorris Broken Cord I continually struggled to understand my little boy as he grew older.
2007 Voice I honestly do feel that my boys are missing out big time on that father figure.

22:38 Dec 7, 2020 

A person in the age of adolescence; a youth. Also: an animal at an analogous stage of development.In earliest use with reference to a young horse.

1663 W. Clark Marciano I will assure you, Ladies, he is an adolescent of eximious candor and egregious integrity.
1783 Hibernian Mag. On the Reverse is the Head of an Adolescent, with flowing Hair, and the Cap of Liberty.
1815 W. Taylor Conveying, without indecency, to adolescents many facts concerning the human frame.
1863 Boston Daily Advertiser Harvard..whose morning bell has murdered sleep for so many generations of drowsy adolescents, is at its post.
1903 Amer. Anthropologist With few exceptions the divisions occur in young or adolescent monkeys, occlusion evidently taking place early in life.
1964 A. Nin Collages Within the mature woman a young and virginal adolescent was still sleeping under her first communion and wedding dress innocence.
2001 Oldie Nature wants children to fly the nest, so it has made adolescents so frightful that parents can't wait to kick them out.

21:40 Dec 7, 2020 

Actually, I myself have kinda thawed towards 'boyhood'. Of course, I'm not qualified to say how old-fashioned it really sounds (though Google Ngram search seems to suggest its usage compared to 'adolescence' is waning, see https://cutt.ly/VhWceIu) to a native ear. What's important here is that you don't need to use 'boy' per se. Substituting 'boyhood' for 'boy' in your second line seems perfectly acceptable to me (def. much more than my previous, more radical suggestion)

Upd: the link is broken, but you can search the Ngram viewer yourself for boyhood vs, for example, adolescence

19:20 Dec 6, 2020 

Many contemporary and obscure words, where a well-known archaic word is clearly required.
Good old Roget suggested: youngster. Archaic enough.

15:14 Dec 6, 2020 

I believe none of the options suggested so far would work because of the cultural/linguistic discrepancy.

You might want to play with adolescence vs puberty, the idea being that few people talk about so-called teenagers being fully biologically mature individuals capable of creating a family (and thus, like they did and still do in more traditional societies , expected to provide for themselves), focusing instead on their artificially prolonged quasi-childhood. Though that would, indeed, be a significant (but not uncalled-for) departure that your particular situation might or might not allow, even with an extensive footnote.