Ubicumque mater sedet, infans ad eam currit.

-cumque adds the idea of ever or soever. So ubi means where, while ubicumque means wherever.

It often introduces a clause that means in any place where or no matter where:

• Ubicumque mater sedet = wherever the mother sits

Mater is the subject of sedet, so it has to be in the nominative.

In the clause ubicumque mater sedet, the mother is the one doing the sitting, so mater is nominative singular.

Sedet is 3rd person singular present indicative active of sedēre, meaning to sit.

So mater sedet means:

• the mother sits
• or, in a more general sense, the mother is sitting

Because it is present tense, it can also express a repeated or habitual action depending on context.

Latin does not have articles like English the or a/an.

So:

• mater can mean mother, a mother, or the mother
• infans can mean infant, a baby, or the baby

You figure out which is meant from the context.

Infans is nominative singular, because it is the subject of currit.

It is a 3rd-declension noun. It can refer to a male or female child, so its natural gender depends on the child being talked about, even though the form itself is the same.

In this sentence:

• infans currit = the infant runs

Because currit is a verb of motion, and Latin often uses ad + accusative to show motion toward someone or something.

So:

• ad eam = to her / toward her

If you only had eam, that would just be her as a direct object, which would not fit the idea of running to her as naturally.

Because ad takes the accusative case.

The pronoun here refers back to mater, which is feminine singular. The feminine singular accusative form of is, ea, id is eam.

So:

• ea = nominative or ablative feminine singular
• eam = accusative feminine singular

Since ad requires the accusative, ad eam is correct.

Yes. Latin could say infans ad matrem currit.

Using eam avoids repeating the noun and sounds more natural in context, just like English often says to her instead of repeating to the mother.

So both are possible:

• infans ad eam currit
• infans ad matrem currit

The version with eam simply refers back to mater.

Currit is 3rd person singular present indicative active of currere, meaning to run.

So infans currit means the infant runs or the infant is running.

In this sentence, the present tense most naturally has a general or habitual sense:

• Whenever/wherever the mother sits, the baby runs to her

So it is not just one single event; it can describe something that regularly happens.

Because the sentence is stating something as a real or regular fact, so the indicative is natural.

Latin often uses ubicumque with the indicative when the meaning is straightforward and factual:

• Ubicumque mater sedet, infans ad eam currit.

A subjunctive could appear in other kinds of contexts, especially if the clause were more dependent on another construction or had a different nuance. But in a simple statement like this, the indicative is exactly what you would expect.

Latin word order is fairly flexible. The sentence could be rearranged, but the cases and verb endings would still show who is doing what.

This version is very natural:

• Ubicumque mater sedet, infans ad eam currit.

It puts the wherever-clause first, then the main clause. That is also a common pattern in English.

The order also helps the sentence flow clearly:

1. first the setting: wherever the mother sits
2. then the result/action: the infant runs to her

So the word order is not the only possible one, but it is a very normal and readable one.