Why ‘mummy’ and ‘papa’ have Bilabial sounds in most languages?

First, let’s collect some words used in different languages to say Mother or Father.

Mother:

Mom, Mummy, Amma, Maa, Ammi, Mater, Mama, Matra, Mere, Awwa, Ammijaan

Father:

Papa, Paa, Padre, Pere, Pitaji, Appa, Pitra, Baba, Pater, Fader, Vader, Abbajaan

Think about what were your first words as an infant.
In most cases, children are taught to say words that stand for mother and father as their first words. And what do most kids do? Imitate. They observe the lip movements of whoever is teaching them those words.

The easiest sounds for a baby to learn or imitate are Bilabials - sounds produced by closure or near closure of both the lips

‘bi’ + ‘labial’

Bilabial sounds as ‘p’, ‘b’, ‘m’, ‘w’
Please do not pronounce them as ‘pii’, ‘bee’, ‘em’ and ‘double u’
We are not speaking about English alphabets, but just sounds.
So, they can be pronounced as - ‘pa’, ‘ba’, ‘ma’, ‘wa’

After, the bilabials, the next easiest sound for a baby are the Labio-dental sounds. As the name suggests, it’s a sound produced by the contact of the lower lip with the upper teeth.

‘Labio’ + ‘ Dental’
Sounds like ‘f’, ‘v’
Now again, it’s not ‘ef’ or ‘vi’, but ‘pha’ and ‘va’

Now, go back and check all the words listed for Father and Mother – they serve the language learning purpose for toddlers. And that’s why most languages uses bilabials or labio-dental sounds for father and mother.

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