Cum liberi lassi sint, tamen hilaritas matris eos laetiores facit.

Here cum introduces a subordinate clause: Cum liberi lassi sint.

In this sentence, cum is best understood as although / while rather than the preposition meaning with. A learner often first meets cum as a preposition with the ablative, but here it is a conjunction.

Because the main clause has tamen (nevertheless / still), the sense is especially concessive:

• cum ... tamen ... = although ... nevertheless ...

So the structure is roughly:

• Although the children are tired, nevertheless the mother’s cheerfulness makes them happier.

Sint is the present subjunctive of esse.

After cum, Latin often uses the subjunctive, especially in clauses that give background, cause, concession, or circumstance. Here the clause is concessive:

• Cum liberi lassi sint = Although the children are tired

If it were cum liberi lassi sunt, that would not fit the standard classical pattern for this kind of clause.

So the key point is:

• cum
  • subjunctive is very common for a subordinate clause of this type
• sint is simply the expected subjunctive form

Tamen means nevertheless, still, or all the same.

It works with the cum clause to emphasize contrast:

• Cum liberi lassi sint, tamen ...
• Although the children are tired, nevertheless ...

Latin often likes this pairing, even when English might leave out nevertheless. It makes the opposition very clear:

• tired children on one side
• the mother’s cheerfulness making them happier on the other

So tamen is not required in every translation into English, but in Latin it is a natural way to mark the contrast strongly.

Liberi is nominative plural masculine.

You can tell because it is the subject of sint in the subordinate clause:

• liberi = the children
• sint = are / may be in the subjunctive

Also, lassi agrees with liberi, which confirms the case and number:

• liberi lassi = the tired children or the children are tired

A common beginner confusion is that liberi can also look like the plural of liber meaning book, but here it means children because of the context and because liberi as a noun commonly means children.

Lassi is an adjective meaning tired. It is nominative plural masculine so that it agrees with liberi.

In the clause:

• liberi lassi sint

lassi is a predicate adjective, not just an attributive adjective. In other words, it is part of the statement the children are tired, not merely the tired children as a noun phrase in isolation.

So:

• liberi = subject
• sint = linking verb
• lassi = predicate adjective describing the subject

Matris is genitive singular, meaning of the mother.

So:

• hilaritas = cheerfulness
• matris = of the mother
• hilaritas matris = the mother’s cheerfulness

Latin often expresses possession with the genitive rather than with a separate word like English ’s.

If you used mater instead, that would be nominative, and the structure would be different. But here the main subject is hilaritas, not mater.

So the main clause is literally:

• the cheerfulness of the mother makes them happier

Eos is accusative plural masculine.

It is the direct object of facit:

• hilaritas matris eos laetiores facit
• the mother’s cheerfulness makes them happier

Here eos refers back to liberi. Latin often uses a pronoun in the main clause to refer to a noun already mentioned in a subordinate clause.

So the pattern is:

• liberi in the subordinate clause
• eos in the main clause

This is perfectly normal and helps Latin keep the grammar clear.

Laetiores is the comparative form of laetus, meaning happier.

The sentence is not saying that the mother’s cheerfulness makes them simply happy, but happier. That comparative idea is important.

Also, laetiores is accusative plural masculine, agreeing with eos:

• eos laetiores facit = makes them happier

So both the case and the comparative meaning matter here.

With verbs like facere (to make), Latin often uses:

• a direct object
• plus another word that describes what that object becomes

So in:

• eos laetiores facit

we have:

• eos = the people affected
• laetiores = what they are made to be
• facit = makes

This is similar to English:

• She makes them happier

So laetiores is not a separate object; it is a complement describing eos.

Good question: laetiores can indeed be either nominative plural or accusative plural for masculine/feminine comparatives.

Here it must be accusative plural, because it goes with eos, which is accusative plural:

• eos laetiores facit = makes them happier

The verb facit takes eos as its object, and laetiores agrees with that object.

So even though the form itself could be ambiguous in isolation, the syntax makes the case clear.

The subordinate clause is:

• Cum liberi lassi sint

The main clause is:

• tamen hilaritas matris eos laetiores facit

A useful way to analyze the sentence is:

1. Cum liberi lassi sint
   background/concessive clause: although the children are tired

2. tamen hilaritas matris eos laetiores facit
   main statement: nevertheless the mother’s cheerfulness makes them happier

This kind of division helps you see where each verb belongs:

• sint belongs to the cum clause
• facit belongs to the main clause

It could, in some contexts, be translated more loosely as when or while, because cum is a flexible conjunction. However, in this sentence the presence of tamen strongly points toward a concessive sense:

• although ... nevertheless ...

That is why although is the most natural interpretation here.

Without tamen, the clause might be felt more generally as a circumstance clause, depending on context. But with tamen, the contrast is front and center.

Latin certainly could repeat the noun in some contexts, but using eos is very natural and often smoother.

Compare:

• Cum liberi lassi sint, tamen hilaritas matris eos laetiores facit.

The pronoun avoids unnecessary repetition and clearly refers back to the children already mentioned.

English does this too:

• Although the children are tired, the mother’s cheerfulness makes them happier
• We would not usually repeat the children again right away unless we wanted extra emphasis

So eos is both normal and elegant.

Yes, but it is also very typical Latin word order.

Latin is more flexible than English because case endings show grammatical relationships. This sentence is arranged in a very readable way:

• Cum liberi lassi sint
  the subordinate clause comes first

• tamen
  marks the contrast at the start of the main clause

• hilaritas matris
  the subject of the main clause

• eos laetiores
  object plus complement

• facit
  the verb comes at the end, which is very common in Latin

So the order helps the sentence unfold clearly:

1. set up the situation
2. mark the contrast
3. give the subject
4. show the effect on the object
5. finish with the verb

This is a concessive cum clause.

A concessive clause expresses an idea like:

• although
• even though

That fits the sentence because the first clause presents something that might seem to work against the result:

• the children are tired

but the main clause says that, in spite of that:

• the mother’s cheerfulness makes them happier

So the grammar and the meaning line up neatly:

• cum
  • subjunctive
• often with tamen in the main clause
• giving a concessive sense: although ... nevertheless ...