اختي كانت عم تغسل شعرها لما وصلت رسالة عالتلفون.

Because Arabic usually adds possessive endings directly to the noun.

• أخت / اخت = sister
• -ي = my

So اختي means my sister.

This is very common in Arabic. For example:

• بيتي = my house
• صاحبي = my friend
• كتابي = my book

In informal Levantine writing, people often leave out the hamza, so اختي is a very normal casual spelling.

• More formal / standard spelling: أختي
• Casual dialect spelling: اختي

They mean the same thing. In chat messages and everyday dialect writing, omitting hamza is extremely common.

This is the Levantine way to express the past continuous: was doing something.

Breakdown:

• كانت = she was
• عم = marks an ongoing action
• تغسل = wash / is washing

So كانت عم تغسل means she was washing.

This pattern is very common in Levantine:

• كان عم يدرس = he was studying
• كانت عم تحكي = she was talking
• كنا عم ناكل = we were eating

Because the subject is my sister, which is feminine singular.

In Levantine, the imperfect verb for she often begins with تـ. So:

• هي تغسل = she washes / she is washing

In this sentence, the subject she is understood from اختي, so Arabic does not need to repeat هي.

Also, this form can look the same as the you (masculine singular) form, so context tells you which one is meant. Here, because of اختي, it clearly means she washes / she was washing.

It has two parts:

• شعر = hair
• -ها = her

So شعرها means her hair.

Arabic very often attaches object and possessive pronouns directly to words instead of using separate words like English does.

Here, لما means when.

It introduces the event that happened during the ongoing action:

• كانت عم تغسل شعرها = she was washing her hair
• لما وصلت رسالة = when a message arrived

So it works a lot like English when in a sentence such as She was washing her hair when a message arrived.

Because verb-first order is very common in Arabic, especially in narration.

So:

• وصلت رسالة = a message arrived

Here:

• وصلت = arrived
• رسالة = a message

Also, رسالة is feminine singular, so the verb is feminine singular too: وصلت.

You could also say رسالة وصلت, but that sounds more marked or more focused on the message itself. The verb-first version is very natural in storytelling.

Yes, very natural.

It literally means a message arrived, and that is a normal Arabic way to express that a message came in or was received.

Other common Levantine alternatives include:

• إجت رسالة = a message came
• إجا مسج = a message/text came
• وصلها رسالة = she received a message / a message reached her

So وصلت رسالة is perfectly good, natural Levantine.

Because in spoken Levantine, على is very often reduced, and when it comes before الـ, the result is commonly written as عالـ.

So:

• على التلفون becomes عالتلفون

This is very normal in dialect writing and speech.

You will see the same thing in many other phrases:

• عالبيت = على البيت
• عالطاولة = على الطاولة
• عالشارع = على الشارع

Because Arabic often leaves possession understood from context.

In English, you might naturally say on her phone, but in Arabic عالتلفون can be enough if the context already makes it clear whose phone is meant.

Since the sentence is about my sister, the listener will usually understand that the message arrived on her phone.

If you want to make it fully explicit, you could say:

• ع تلفونها = on her phone

In this context, yes, that is the natural interpretation, because messages normally arrive on a mobile phone.

But تلفون itself is a general word for phone. Depending on the speaker and region, you might also hear:

• موبايل = mobile phone
• جوال = mobile phone (more common in some regions than others)

So a speaker might also say something like:

• وصلت رسالة عالموبايل
• إجاها مسج عالموبايل

But عالتلفون is still completely understandable and natural.