Hindi ka mag-iisa, sis! A few of us have babies na ganyan din, madaldal at responsive sa voice pero selective lang talaga sa paggaya ng gestures o words, and that's actually okay pa rin sa age na yan. Pero since baby mo is 9 months na at ang communication skills ay importante, I'd say it's worth bringing up sa pediatrician lang para ma-check properly, baka may hearing concern or developmental thing na kailangan monitor, or baka normal lang talaga at reassurance lang kailangan mo. Most of our moms swear na once na sinabi ng doc na okay, napawi na agad ang worry, so don't stress too much muna but do get it checked para peace of mind.