Mama alimkumbatia mtoto na kumbusu shavuni.

It can be broken down like this:

• a- = he/she
• -li- = past tense
• -m- = him/her (object marker for a singular person)
• -kumbatia = hug / embrace

So alimkumbatia literally means he/she hugged him/her.
Because the subject here is Mama, the full sense is Mother/Mum hugged him/her.

That -m- is an object marker. In Swahili, it is very common to include an object marker on the verb even when the full object noun also appears, especially when the object is:

• human
• specific
• already clear in the context

So alimkumbatia mtoto is not redundant in a bad way. It is a very natural Swahili pattern: the verb already points to him/her, and then mtoto tells you exactly who that person is.

Neither specifically. Mtoto just means child, and it does not tell you the sex of the child.

If Swahili wants to be more specific, it can use words like:

• mvulana = boy
• msichana = girl

The plural of mtoto is watoto = children.

Here, kumbusu can be analyzed as:

• ku-
• -m- = him/her
• -busu = kiss

The basic dictionary verb is kubusu = to kiss.
When the object marker -m- is inserted, it becomes kum-busu / kumbusu = to kiss him/her.

So in this sentence, it means and kiss him/her or more naturally and kissed him/her.

Because Swahili often avoids repeating a full finite verb when the same subject continues and the verbs are linked by na.

So after Mama alimkumbatia mtoto, the shorter na kumbusu shavuni is understood as continuing the same subject:

• Mama hugged the child
• and kissed him/her on the cheek

A fuller version could be something like Mama alimkumbatia mtoto na akambusu shavuni, but the shorter version is perfectly normal.

Na means and.

Here it links two actions done by the same subject:

• alimkumbatia = hugged him/her
• kumbusu = kissed him/her

So it joins the two actions in sequence: hugged the child and kissed him/her...

Shavu means cheek.
The ending -ni is a locative ending, which often gives a sense like:

• in
• on
• at

So shavuni means something like:

• on the cheek
• at the cheek

In natural English, on the cheek is the best translation here.

In this sentence, it means kiss the child on the cheek.

Why? Because the object marker -m- in kumbusu refers to the child. That is the person receiving the kiss.

Then shavuni tells you where the kiss landed: on the cheek.

So the structure is basically:

• kumbusu = kiss him/her
• shavuni = on the cheek

Sometimes, yes. Swahili can sometimes say a verb with the full object noun and no object marker. But with a specific human object, using the object marker is very common and natural.

So:

• alimkumbatia mtoto sounds very natural
• alikumbatia mtoto may also be possible in some contexts

The version with -m- strongly signals that the object is a definite, identifiable person.

Mama can mean mother, mum, or mom, depending on context and translation style.

It can also be used as a respectful way to refer to a woman, but in this sentence the most natural meaning is simply mother/mum.

So English could translate it as:

• Mother
• Mum
• Mom

depending on the tone you want.