tiisai inu ga ie kara nigeta node, ane to issyo ni tukamaemasita.

Yes. 小さい is an i-adjective, and it directly modifies the noun 犬.

So:

• 小さい犬 = small dog

This works much like English small dog. You do not need の between them.

A learner may also notice 小さな犬 exists too. That is also possible, but 小さい犬 is the more basic and regular form.

が marks 犬 as the grammatical subject of 逃げた.

So in the first part:

• 小さい犬が逃げた = the small dog ran away

Using が here puts focus on the dog as the thing that did the action.

If you used は, the nuance would be different. は would make the small dog the topic, while が more directly marks it as the subject in this specific event. In a sentence like this, が sounds very natural.

から means from.

So:

• 家から逃げた = ran away from the house/home

It marks the starting point or place something moves away from.

Other examples:

• 学校から帰る = return from school
• 椅子から立つ = stand up from a chair

Here, the dog escaped starting from 家.

Because the sentence is talking about a completed event: the dog ran away / escaped, and because of that, the speaker caught it.

So:

• 逃げた = escaped / ran away
• 逃げたので = because it escaped

The past form in the reason clause matches the fact that the escape happened before the catching.

If you said 逃げるので, it would sound more like because it will run away / because it runs away, which does not fit this context as naturally.

Here, ので means because or so.

• 逃げたので、捕まえました = Because it ran away, I caught it

Compared with sentence-ending から meaning because, ので usually sounds:

• a bit softer
• a bit more explanatory
• a bit less blunt

So:

• 逃げたから、捕まえました = also correct
• 逃げたので、捕まえました = slightly more neutral/explanatory

Both are common, but ので often feels smoother in narration.

This is completely normal in Japanese.

In a sentence with a subordinate clause like 〜ので, the verb before ので is usually in plain form:

• 逃げたので

The main sentence can still be polite:

• 捕まえました

So the pattern is:

• subordinate clause: plain
• main clause: polite if the overall sentence is polite

This is one of the most common patterns in Japanese.

The subject is omitted because Japanese often leaves out information that is clear from context.

So 捕まえました could mean:

• I caught it
• we caught it
• sometimes another understood subject, depending on context

Because the sentence says 姉と一緒に, the most natural interpretation is:

• I caught it together with my older sister

Japanese very often omits I, we, he, she, and even it when they are understood.

Yes, if you say the object explicitly, you would normally say:

• 小さい犬を捕まえました

But in this sentence, the object is omitted because it is already obvious: the thing that escaped is the thing that was caught.

So Japanese naturally leaves it out:

• 逃げたので、姉と一緒に捕まえました

This is very common. English usually repeats it, but Japanese often does not.

姉 means my older sister.

Japanese often uses different words depending on whether you are talking about:

• your own family
• someone else’s family
• speaking directly to that person

In general:

• 姉 = my older sister
• お姉さん = someone else’s older sister, or a respectful/polite form

So in this sentence, 姉 is natural because the speaker is talking about their own older sister.

Because they work together as a set meaning together with.

• 姉と = with my older sister
• 一緒に = together

So:

• 姉と一緒に = together with my older sister

You will often see this full pattern. It makes the meaning very clear.

Sometimes と by itself can mean with, but 一緒に emphasizes doing something together.

It is the polite past form of 捕まえる, which means to catch or to capture.

Breakdown:

• dictionary form: 捕まえる
• polite non-past: 捕まえます
• polite past: 捕まえました

This is an ichidan verb.

So:

• 捕まえました = caught

It can mean both, depending on context.

逃げる often means:

• run away
• flee
• escape

In this sentence, because it is a dog and it is from the house, natural English could be:

• ran away
• got loose
• escaped

All of these are close in meaning here.

A simple way to divide it is:

• 小さい犬が家から逃げたので
  = because the small dog ran away from the house

• 姉と一緒に捕まえました
  = I caught it together with my older sister

So the overall pattern is:

• reason + ので + main action

This is a very common Japanese sentence pattern.