for your sister's birthday
for your sister
prep det:poss adj
for your sister's birthday ?
f ɔː ɹ WORD_BOUNDARY j ʊ ɹ WORD_BOUNDARY s ɪ s t ɚ z WORD_BOUNDARY b ɜː θ d eɪ WORD_BOUNDARY
f o r WORD_BOUNDARY y o u r WORD_BOUNDARY s i s t e r ' s WORD_BOUNDARY b i r t h d a y WORD_BOUNDARY