Mama/dada effect: Children everywhere in the world say mamamama as their first syllable, which is why mama means mother both in Chinese and in anglo-franco-hispanic-germanic-latin languages, and everywhere else. They then say dada, baba, papa, which is why baba means dad in both China and in latin languages. Ramachandran and Hubbard suggest that the kiki/bouba effect has implications for the evolution of language, be…
Which is to say - there's no single "first syllable" and "second syllable" that all babies say in that exact order. They just babble, and adults interpret those noises as syllables according to the phonemics of their language. Thus results may vary.