Even so -- (CW) The word translated in KJV as "even so" is in its adverbial form, so it means "in this manner" or "in this way."

it -- This is from the third-person, singular form of the verb.

is -- This is from the third-person, singular form of the verb.

not  - The Greek word translated as "not" is the Greek negative used to deny objective facts, not opinions. In fact, it really makes a negative statement of fact something like adding "really" and "in fact" in English.

the -- (IW) There is nothing that can be translated as "the" in the Greek source. The sense here is "a desire."

will  -- The Greek word translated as "will" primarily expresses consent and even delight in doing something.  The sense here is "desire" thought it could be stretched to "decision." It is not preceded by an article so "a desire" or "a decision."

of -- (WW) The Greek word translated as "of" means "in front of" referring to place and when used to apply to time means "beforehand." This is not the "of" of possession, but a preposition of place and time. This is not the way Jesus says "my Father's will," which is something he says frequently. The sense here is that this is not something that the Father desires at all.

your -- "My" is the first-person possessive singular pronoun. This pronoun follows the noun so "of mine."

missing "the"  -- (MW) The untranslated word is the Greek definite article, "the." The Greek article is much closer to our demonstrative pronouns ("this," "that," "these," "those"). See this article for more. 

Father -- "Father" is the Greek noun that means "father" or any male ancestor so "forefathers." It is the word that Christ uses to address his own Father. 

which -- The word translated as "which" is the Greek definite article, which when not preceding a noun, takes the meaning of "the one" or, in the plural, "the ones." The Greek article is much closer to our demonstrative pronouns ("this," "that," "these," "those"). See this article for more. 

is -- (IW) There is nothing that can be translated as "is" in the Greek source.

in - The word translated as "in" means "in," "within," "with," "during" (time),  or "among"  with a dative object as the one here.

heaven, -- The word translated as "heaven" means sky, the climate, and the universe. It also meant the home of the gods in a physical sense: the sun, moon, and planets were named for the gods. More about the word in this article.

that -- The word translated as "that" is an adverb "in that place," "there," "where," "when," or as a conjunction that starts a subordinate clause  "that," "when," "in order that" or "because."

one-- The Greek word translated as "one " means "one" (as opposed to other numbers), "single," and "one and the same."As in English, it can be used as a pronoun, meaning a single person.

of -- This word "of"  comes from the genitive case of the following word that requires the addition of a preposition in English.  The most common is the "of" of possession.

these -- "These" is a demonstrative pronoun that means "this," "here," "the nearer," and "the familiar."

little  - "Little ones" is from an adjective which means "small," "little," and "young." Christ uses it to refer to children, but also to his followers. The sheep in the previous two verses were also symbolic of his followers.

ones -- The word translated as "ones" is the Greek definite article, which when not preceding a noun, takes the meaning of "the one" or, in the plural, "the ones." The Greek article is much closer to our demonstrative pronouns ("this," "that," "these," "those"). See this article for more. 

should --  This helping verb "should" does not indicate the future tense, but that the verb describes a possibility, the subjunctive voice. A "might" or "should" in English is more appropriate, but is assumed in an "if/when/whoever/except" clause. Helping verbs are not needed in Greek since the main verb carries this information in its form.

perish  - (WW) "Perish" is from a verb that is a very strong form of "to destroy," "to kill," and "to lose." It means "to destroy utterly." Most importantly, this verb is in the passive, so "be destroyed," or the middle voice, "destroy themselves." These senses are destroyed by translating it as "perish."