Previously, my baby wakes up at 10pm, 3am and 5am to drink her milk. But just last week, she doesn't wake up anymore and enjoys sleeping longer hours instead. Is this normal to all babies?

It differs from baby to baby. My baby managed to sleep through when he was 3 mths old till now (2.5yrs old). It is a relief because I can get enough rest too. However, there were also times that he wakes up for milk which I didn't give in. I merely patted him back to sleep.