The spelling of "Rehbein" can be explained using the International Phonetic Alphabet (IPA), which represents the sounds of spoken language. In IPA, "Rehbein" is pronounced /ˈɹeɪbaɪn/, with the stress on the first syllable. The first sound, /ɹ/, is the "r" sound in English. The second sound, /eɪ/, is a diphthong, a combination of the sounds "ay". The next sound, /b/, is the "b" sound, followed by /aɪ/, which is another diphthong, a combination of "ai". Finally, the word ends with the /n/ sound.
"Rehbein" is not an English word, and I was unable to find any information on its etymology. It is possible that "Rehbein" is a proper noun or a surname, which may have different origins and meanings.